Cybersecurity affects us all in our daily lives. New knowledge on best practices, new vulnerabilities, and timely fixes for cybersecurity issues is growing super-linearly, and is spread across numerous, heterogeneous sources. Because of that, community contribution-based, question and answer sites have become clearinghouses for cybersecurity-related inquiries, as they have for many other topics. Historically, Stack Overflow has been the most popular platform for different kinds of technical questions, including for cybersecurity. That has been changing, however, with the advent of Security Stack Exchange, a site specifically designed for cybersecurity-related questions and answers. More recently, some cybersecurity-related subreddits of Reddit, have become hubs for cybersecurity-related questions and discussions. The availability of multiple overlapping communities has created a complex terrain to navigate for someone looking for an answer to a cybersecurity question. In this paper, we investigate how and why people choose among three prominent, overlapping, question and answer communities, for their cybersecurity knowledge needs. We aggregated data of several consecutive years of cybersecurity-related questions from Stack Overflow, Security Stack Exchange, and Reddit, and performed statistical, linguistic, and longitudinal analysis. To triangulate the results, we also conducted user surveys. We found that the user behavior across those three communities is different, in most cases. Likewise, cybersecurity-related questions asked on the three sites are different, more technical on Security Stack Exchange and Stack Overflow, and more subjective and personal on Reddit. Moreover, there appears to have been a differentiation of the communities along the same lines, accompanied by overall popularity trends suggestive of Stack Overflow’s decline and Security Stack Exchange’s rise within the cybersecurity community. Reddit is addressing the more subjective, discussion type needs of the lay community, and is growing rapidly. The state-of-the-art in cybersecurity knowledge is an ever-expanding horizon. New cybersecurity exploits are constantly being discovered and reported, software patches are created and released, and people learn about them and patch their own systems. This growing wealth of information is being stored in different places and is available publicly. The CVE database  is one oBecause of the many different sources where information about cybersecurity is stored, and its high volume and longitudinal nature, finding the most current and accurate one can be a real challenge. For example, the Heartbleed Bug  was a seInstead of directly searching for information at the source and then processing the findings, for a while now the social web has been providing marketplaces for bringing together people with questions and people with answers. Social question and answer (Q&A) sites like Stack Exchange (SE)  in generThe similar structures and functionalities of these sites, as well as their overlap, can present a challenge for novice users looking for information. For example, here are three cybersecurity-related questions: “Is it secure to use “require” with GET/POST data?”, “What’s the difference between MAC algorithm vs hash algorithm?”, and “Which email provider is the best in terms of security and privacy?”. Although each of them can be asked in either of the three platforms, we do not know which platform is the most suitable one for each question. The following, then, arise naturally: what type of cybersecurity-related information do people get from each site? Are the sites used interchangeably or complementarily? Which of those sites are the most popular and for what?Sec SO (cybersecurity sub-parts of Stack Overflow), Sec SE (Security Stack Exchange site 72] to exThere exist many bot accounts in Reddit which can post and comment just like humans do. To remove bot posts, we followed a procedure similar to that used in prior work , as follhttps://zenodo.org/record/5260017. Here, we only show the data statistics of the six overlapping years since the time span of our Sec Reddit data is shorter than that of Sec SO and Sec SE. We restrict the Sec SO data and Sec SE data to the same time range as Sec Reddit’s data for most experiments except RQ3. For Sec SO and Sec SE, we define “unique participants” as those users who have ever posted questions/answers/comments. For Sec Reddit, we define “unique participants” as users who have ever posted posts/comments in Sec Reddit.Descriptive statistics of the data we gathered is shown in Sec SO/Sec SE data and treat all comments as “answers” for Sec Reddit data, regardless of the nesting level.The structures of a Reddit text post and a Stack Exchange post are somewhat different. In Reddit, a text post is followed by zero or more “comments”. Each comment can have multiple levels of other nested comments. On the other hand, a Stack Exchange post is followed by zero or more “answers”. Each post, and the answers to it, can have multiple non-nested comments. “Comments” in Reddit are sometimes answers and sometimes are just comments on the post or other comments. To appropriately compare the activity across the three sites, we treat both answers and comments as “answers” for To compare the questions being asked in one site vs. the others, we utilize a qualitative, manual sample examination approach, a quantitative, machine learning/NLP approach, and a quantitative, statistical approach. The goal of the qualitative approach was to identify broad categories  for the questions based on broad concepts in them, and of the quantitative approaches was to determine the similarity between the sites based on linguistic properties of the questions asked on them.We first sought to identify concrete topical question categories, not only restricted to distinguishing between informational and conversational questions . We chosTo determine the semantic similarity between questions on one site and those on another, we first use an NLP approach. BERT , which wWe first preprocess all text posts from those three social Q&A sites. Following the practice of , 81, we In our second quantitative approach, we use a Venn diagram. For each site, we count the most frequently appearing 100 words, after removing common stop words and lemmatization  of all appeared word. Then we draw a 3-circle Venn diagram to visually show the number of overlapping words between the three sites. In general, if a pair of websites has more overlapping words than other pairs, it suggests that this pair is semantically closer than the other pairs of websites.https://forms.gle/arZWN7ZR6PhLREyk7).We augmented the quantitative experiment with an online user survey to triangulate the quantitative findings. We wanted to understand the real users’ experiences of participating in those three cybersecurity communities and the underlying reasons of the community migration, if they in fact migrated. We asked participants for: if they used each site, how often do they go/participate each Q&A site, the purpose of using each Q&A site, their satisfaction with the answers they get, and their site migration behaviors. The detailed user survey is shown in this link  from each of the three social Q&A sites. Every Reddit participant is reachable through a private message on Reddit. However, Stack Overflow and Security Stack Exchange do not have the functionality of direct communicating with someone. Instead, we identified reachable participants as those whose emails can be acquired in one of the two ways: (1) directly available on their personal profile page or (2) is available in a corresponding GitHub account when a link to that account is displayed on the user’s personal profile page. Thus, we sent the survey invitations to When we contacted the participants through email and direct messages, participation consent was informed. We indicated our names, affiliation, the academic purpose of the survey (their responses will be used in a research study), and the voluntary and anonymous feature of the survey. Because of this, our online survey was exempt from the full IRB review as limited surveys of social media participants has been deemed exempt if consent was informed and participation voluntary, which was the case in our study.Sec SO, Sec SE, and Sec Reddit, that are related to user participation. Specifically, we study the fraction of answered questions, the latency to the first answer, the number of answerers/answers per question, and the number of questions asked/answered per unique questioner/answerer. For all experiments in this section, we choose the same six-years time range (2015-2020), available for all three sites. We present both aggregate results and longitudinal results. For all three sites, we exclude answers posted by the questioners themselves in each question.We first seek to characterize the similarities and differences in question answering, across Sec SO and 2,147 questions in Sec SE being deleted because of this.We start by comparing across the three sites the fraction of questions receiving answers within half year (182 days). Half year is chosen for a fair comparison between questions posted in each year. We include in our counts those deleted questions which were posted in 2015-2020 and deleted after not receiving an answer in 365 days  of a question. The scope of this analysis is all questions with at least one corresponding answer within 182 days, and we only count answers posted within 182 days.Sec SO and Sec SE are relatively stable over time, especially the former. The only exception is that there is a big drop in 2017 for Sec SE. The variation in the curve for Sec Reddit is larger than it for Sec SO and Sec SE, and there are two big boosts appearing in 2016 and 2018.Sec Reddit are 5.29 and 3, higher than those for questions asked in Sec SE, and much higher than those of Sec SO. The number of answers given by those “unique” answerers shows a similar pattern, with Sec Reddit numbers higher than Sec SE and Sec SO.From the aggregate statistics, in Sec SE, there are only 15,171 unique answerers, much less than the 21,656 unique questioners. For the other two sites, the number of answerers is higher than the number of questioners, especially in Sec Reddit, and by a large margin. The results for Sec SO and Sec Reddit are somewhat expected because there are 1.99 answerers for a Sec SO question on average, and there are 5.29 answerers for a Sec Reddit question. The surprisingly low ratio of the number of unique answerers to the number of unique questioners in Sec SE suggests that on average, each answerer in Sec SE answers many more questions than answerers in Sec SO and Sec Reddit.The number of unique questioners (users who post questions) and unique answerers (users who answer questions) is shown in Sec SO show a smooth decreasing trend, while the corresponding Sec SE curve increases in 2016 and starts decreasing after that. Sec Reddit shows a generally increasing trend. Answerer numbers decrease in Sec SO and Sec SE starting in 2015, and to a lesser extent in Sec SO. The Sec Reddit curve drops drastically in 2016, and then starts climbing up at a slower rate.The participation behavior per year is shown in The aggregate number of questions asked per questioner and the number of questions answered per answerer for the whole five-years time periods are shown in We first look at the behavior of questioners. The first quartile, median, and third quartile for questioners in all those three sites are 1, so we use the unpaired t-test to assess whether the difference in the means is significant. The low P-values (< 0.0001) for each pair  show thaSec SO, the 1.13 mean value and the 0.53 standard deviation value show that most questioners only ask one question with few exceptions. The values for Sec SE and Sec Reddit are similar, with relatively large standard deviation values. This implies that there exists a small number of questioners in Sec SE and Sec Reddit asking more questions.Sec SE, given the other values, the mean of 8.08 and the standard deviation of 63.59 are surprisingly large. This suggests the existence of a small portion of answerers, each answering a large number of questions.Then we look at the number of unique questions each answerer answers to in Sec SO, 96.45% answerers answer 0-5 questions, with few percent of answerers answering more questions. For Sec Reddit, 86.45% answerers answer 0-5 questions, 6.51% answerers answer 6-10 questions, and 6.05% answerers answer 11-50 questions. There are also 0.99% (414) very active answerers answering more than 50 questions. Regarding Sec SE, the percentages are close to those of Sec Reddit for answerers answering 0-5, 6-10, and 11-50 questions, but the percentage of very active answerers answering more than 50 questions in Sec SE is more than double the percentage for Sec Reddit. In particular, there are 2.50% (379) answerers answering more than 50 questions each in Sec SE. Since we didn’t include deleted low-quality answers in our dataset, the above percentage could suggest the existence of many active and knowledgeable answerers who supply many good answers in Sec SE, and thus a higher level of expertise in cybersecurity.We analyze the above distributions at a finer level by looking at the distribution of answerers answering different numbers of questions. The six intervals are 0-5, 6-10, 11-50, 51-100, 101-500, and >500. The result is displayed in Sec SO are answered very quickly but many others are answered very slowly or left unanswered; Questions asked in Sec Reddit have more answerers and answers than those in the other two sites; The percentage of more active and knowledgeable answerers on Sec SE is higher than that of Sec Reddit, and both are much higher than that of Sec SO. However, Sec Reddit activity is increasing over time while Sec SO and Sec SE are decreasing, especially the latterRQ1: Many cybersecurity questions in .Using open card sorting on samples of the data from each site, as described in the Materials and methods section, we found that there are 4 main types of questions on the three sites:Type1: Look for solutions about cybersecurity-related programming questions.Type2: Look for solutions about cybersecurity-related general questions.Type3: Look for advice of career/resume/interview regarding cybersecurity field.Type4: Look for recommendations or user experiences of cybersecurity-related products/software/tutorials/courses.The most popular two types are informational questions  where peThe next two categories of questions are conversational questions  that areSec SO, the first two more objective types of questions contribute to 94.58% of total questions, and 45% of the total questions are programming-related. Similarly, the first two types of questions in Sec SE occupy 91.67% of all questions, with only 17.5% of the total questions are programming-related. The statistics for Sec Reddit is very different. The first two types comprise 46.67% of the total questions, though only 1.67% for Type 1. There are 19.58% of questions on Sec Reddit that are career-related inquiries, while the percentage is 0% and 0.42% for Sec SO and Sec SE. The fourth type of questions in Sec Reddit contributes to 33.75% of the total questions which is much higher than that of Sec SO and Sec SE. The underlying reasons might be that Sec SO and Sec SE have more strict requirements about what should be asked and should not be asked on the sites, whereas Sec Reddit does not have those restrictions. The very low percentage of Type 3 questions on Sec SO and Sec SE may be due to the fact that career-related inquiries are mostly opinion-based, and this is one of the five reasons for questions being closed in Stack Overflow and Security Stack Exchange. The situation for Type 4 questions is similar, and we found some closed Type 4 questions in Sec SO and Sec SE during our manual inspection. “Opinion-based” and “off-topic” are two common reasons for Type 4 questions being closed.The manual classification result of those randomly selected 240 questions for each platform is displayed in The results shown in Sec SO and Sec SE are more semantically similar than any other two pairs of the three sites. The result is not surprising as the first two types (see above) of similar questions contribute to 94.58% and 91.67% questions on Sec SO and Sec SE, and we already removed any code in the pre-processing step of this experiment. Another interesting finding is that questions on Sec Reddit are semantically closer to Sec SE than to Sec SO. The potential reason behind this is that only 1.67% of the questions in Sec Reddit are programming-related, whereas a large fraction of questions on Sec SO are programming-related. We also observe that Sec SO and Sec SE are becoming semantically closer to each other over time, while Sec Reddit is becoming more distant from both.Then, we compare the cosine similarities of embeddings of questions posted in the same year between each pair of websites. Sec SO and Sec SE have 26 additional overlapping frequent words, more than Sec SE and Sec Reddit (only 16). Sec SO and Sec Reddit have only 3 additional overlapping frequent words, the least. This is consistent with the above findings that Sec SO and Sec SE are most semantically similar.Sec SO and Sec SE appear to be technical, with those on Sec SO focusing more on programming. Sec Reddit includes both technical and more subjective or opinion-based questions. Questions on Sec SO and Sec SE are more semantically similar to each other, than questions on Sec Reddit, and growing closer over time. Sec Reddit questions are growing more semantically distant from the othersRQ2: Most questions on .First, we use the number of questions asked, the number of answers given, the number of unique questioners, and the number of unique answerers as indicators for the popularity change of the three sites over time, in monthly intervals.Sec SO is in a generally decreasing trend from 2011 on, though the curve is not very steep. One potential reason is that with the advent of other social Q&A sites hosting cybersecurity-related questions, especially Sec SE, some questioners may turn to ask their cybersecurity questions on social Q&A sites other than Sec SO. For Sec SE, the popularity increases from 2011 to 2016 and reaches its peak during the second half of 2016. This is what we would expect as the Sec SE was created in the second half of 2010. As the site’s popularity increased throughout the years, it likely attracted many questioners from Sec SO. However, since 2017, its popularity has been decreasing. On the contrary, the number of questions being posted on Sec Reddit does not vary much from 2015 to the first half of 2017, but after that, the number has been growing super-linearly until the end of 2019. In the first half of 2020, there is a big drop in the popularity of Sec Reddit. One potential reason might be that r/security  tag is overshadowed by numerous more popular tags. Sec SO are smaller than those in Sec SE. On the other hand, the focus in Sec SE is narrower, limited mostly to cybersecurity-related technical questions. Our result  to understand more fundamentally ecosystems of such overlapping communities, (2) the reasons for the explosive growth of the Reddit cybersecurity community especially in terms of whether a discussion-based knowledge sharing site is more effective than the more traditional question and answer sites, and (3) to measure the level of expertise in the public domain , as a collective output.


Rare cases of co‐existing sarcoidosis and carcinoid tumour have been previously reported in the literature. Both diseases may have vague and overlapping clinical presentations that can lead to delayed or missed diagnosis. To avoid this diagnostic pitfall, we discuss and compare the clinical presentations of all reported cases in the literature including our case. We also provide hypothesis to explain the relationship between the two diseases. In the current report, we describe a rare case diagnosed histologically with sarcoidosis and neuroendocrine tumour. We also describe 23 similar cases previously reported in the literature. We discuss the clinical presentations of the cases and possible hypothesis explaining the association between the two diseases. Although co‐existence of these two diseases is extremely rare, understanding the common clinical presentations and the relationship between the two diseases is important as the diagnosis can easily be missed. Sarcoidosis is a multisystem granulomatous disease of unclear aetiology . SarcoidIn the current report, we describe a rare case diagnosed histologically with sarcoidosis and NET. We also describe 23 similar cases previously reported in the literature. We discuss the clinical presentations of the cases and possible hypothesis explaining the association between the two diseases. Although co‐existence of these two diseases is extremely rare, understanding the common clinical presentations and the relationship between the two diseases is important as the diagnosis can easily be missed.1) of 2.10 L (57% predicted), forced vital capacity (FVC) 3.92 L (86% of predicted), FEV1/FVC 54%, residual volume (RV) 2.38 L (104% predicted), total lung capacity (TLC) 6.61 L(90% predicted), and diffusing capacity of lung for carbon monoxide (DLCO) 16.6 mL/mmHg/min (59% predicted), consistent with a moderate obstruction ventilatory disease with no bronchodilator response. Diagnosis of sarcoidosis was made based on clinical, radiological, and histopathological findings, and after other aetiologies for granulomatous diseases had been ruled out. His bilateral subcentimetre pulmonary nodules were attributed to sarcoidosis. There was no evidence of extrapulmonary organ involvement of sarcoidosis. The patient was started on oral corticosteroids. He was also diagnosed with chronic obstructive pulmonary disease (COPD) given his smoking history and the PFT findings, for which he was started on inhaled bronchodilator therapy. Subsequently, the patient was referred to our sarcoidosis clinic. He continued to have poor appetite, fatigue, wheezing, diarrhoea, and shortness of breath. As weight loss and supraclavicular lymphadenopathy are not typical manifestations of sarcoidosis, surgical lymph node removal of supraclavicular lymph node was undertaken and confirmed the presence of an NET that was positive for chromogranin A and synaptophysin by immunohistochemistry. Semiquantitative proliferative rate (Ki‐67) was <5%. Metastatic workup with gallium‐68 Dotatate positron emission tomography (PET)/CT scan  . Computed tomography (CT) of the chest  with GI NETs have sarcoidosis in hilar‐mediastinal lymph nodes but not in mesenteric lymph nodes where the GI lymphatics drain. This raises an assumption that lymph nodes are not genetically equally predisposed to form sarcoidosis in response to foreign antigens.The second hypothesis is that tumour antigens can induce systemic sarcoidosis in genetically predisposed patients , 9, 10. The third hypothesis is that sarcoidosis increases the risk of malignancy because of chronic inflammation in the affected organs and/or immune dysregulation. Studies provide inconsistent results regarding the incidence of malignancy in sarcoidosis patients from no risk to significantly elevated risk , 5, 6, 7In conclusion, hilar‐mediastinal lymph nodes spread is not typical for NETs and sarcoidosis should be in the differential diagnosis. Also, supraclavicular lymphadenopathy and GI masses are not typical manifestations of sarcoidosis and warrant further investigations to rule out malignancy. We believe that there is a real association between the two entities. We hypothesize that carcinoid tumours induce local and or systemic sarcoidosis. However, further research is needed to understand the relationship between sarcoidosis and NETs and other cancers.Appropriate written informed consent was obtained for publication of this case report and accompanying images.Muhanad Taha: Study conception and design, acquisition of data, analysis and interpretation of data, drafting of manuscript. Lobelia Samavati: Study conception and design, critical revision.


TARDBP gene is an evolutionarily conserved heterogeneous nuclear ribonucleoprotein (hnRNP) that regulates multiple steps of RNA metabolism, and its cytoplasmic aggregation characterizes degenerating motor neurons in amyotrophic lateral sclerosis (ALS). In most ALS cases, cytoplasmic TDP-43 aggregation occurs in the absence of mutations in the coding sequence of TARDBP. Thus, a major challenge in ALS research is to understand the nature of pathological changes occurring in wild-type TDP-43 and to explore upstream events in intracellular and extracellular milieu that promote the pathological transition of TDP-43. Despite the inherent obstacles to analyzing TDP-43 dynamics in in vivo motor neurons due to their anatomical complexity and inaccessibility, recent studies using cellular and animal models have provided important mechanistic insights into potential links between TDP-43 and motor neuron vulnerability in ALS. This review is intended to provide an overview of the current literature on the function and regulation of TDP-43-containing RNP granules or membraneless organelles, as revealed by various models, and to discuss the potential mechanisms by which TDP-43 can cause selective vulnerability of motor neurons in ALS.Transactive response DNA-binding protein 43 kDa (TDP-43) encoded by the  Abnormal aggregation of proteins that normally function as components of ribonucleoprotein (RNP) granules is a hallmark of neurodevelopmental and neurodegenerative diseases –3. UnderTARDBP gene and regulating transcription  –38 35–38RNA binding of TDP-43 is mediated by the two RNA recognition motif (RRM) domains (RRM1 and RRM2) that reside in the middle of the primary protein structure . RRM1 anThe IDR in the C-terminus comprises a glycine-rich domain and a region enriched in glutamine (Q) and asparagine (N). Proteins with IDRs reversibly phase separate into droplets; however, such assembly of IDR proteins may become irreversible when they aggregate due to mutations, prolonged stress, or changes in protein concentration . SupportNuclear bodies (NBs)In mammalian cells, both endogenous TDP-43 and exogenously expressed TDP-43 at a normal endogenous level show a demixed distribution as rounded particles in the nucleus , 63. TDPRNP transport granulesMembraneless organelles formed via condensation of protein–RNA complexes, or phase transition, is relevant for the long-range transport of biomolecules particularly for large-sized and polarized cell types, including motor neurons, where transcription in the nucleus and translation at the synapse can be as far apart as the entire length of the spinal cord, arms, or legs. A fraction of cytoplasmic TDP-43 in neuronal cells functions as a component of RNP granules that undergo microtubule-dependent transport along the axon , 78. ExoSGsTo sustain cell survival, global repression of translation occurs in response to cellular stresses. SGs are cytoprotective membraneless organelles comprising RNA–protein complexes, and seen in the cytoplasm of cells under stress , 82. TDPTDP-43 in myo-granulesCytoplasmic TDP-43 granules have been shown to play important physiological roles in skeletal muscles. Reduced levels of TDP-43 in skeletal muscles lead to age-related muscle weakness in mice and flies –88 and tPathological TDP-43 aggregatesC9orf72 locus carrying repeat expansions, a cause of familial ALS, also causes TDP-43 aggregation [Cytoplasmic inclusions of TDP-43, appearing as rounded or skein-like inclusions in degenerating neurons, are a reliable pathological hallmark of ALS and FTLD-TDP , 94. In regation –102. Intregation , 104. Ofregation , hintingregation . Interceregation –106. In regation . Microveregation , 103, whregation .In sporadic ALS, pathological TDP-43 phosphorylation recognized by the pS409/S410 antibody is observed throughout many areas of the central nervous system (CNS) , showingNeural activity-dependent alternative splicing of TDP-43Motor neurons are large cells with large membrane surface areas, which demand high levels of energy for generating an action potential, as well as for maintaining homeostatic ionic gradients across the plasma membrane in the resting state. The energetic demand is particularly high in large fast-fatigable motor neurons, the most vulnerable neuronal type in ALS , and theCa2+-dependent cleavage of TDP-432+ levels caused by excessive stimulation of glutamate receptors have been implicated in the selective vulnerability of neurons in ALS [2+-permeable subunits GluA1, 3, and 4 and the typically Ca2+-impermeable subunit GluA2 [2+-impermeable GluA2 subunit [2+ influx could lead to TDP-43 aggregation. The observation that TDP-43 is subject to proteolysis in a Ca2+ -dependent manner provides a mechanistic link between the exaggerated Ca2+ influx and TDP-43 aggregation [2+-dependent cysteine proteases) at the C-terminus, which is distinct from the caspase-dependent cleavage sites 2+ levelsTDP-43 and mitochondria2+ homeostasis, which is regulated through interactions between the endoplasmic reticulum (ER) and mitochondria via a region in the ER called mitochondria-associated membranes (MAM) [2+ overload in mitochondria, whereas its loosening diminishes mitochondrial ATP synthesis and increases cytosolic Ca2+ [2+ could in turn induce calpain-mediated cleavage of TDP-43, leading to TDP-43 aggregation [2+ homeostasis, whose dysfunction could contribute to selective vulnerability of motor neurons in ALS.The high energetic demand of motor neurons is met by ATP provision via mitochondrial metabolism. Inevitably, mitochondria are major sources of reactive oxygen species (ROS) within most mammalian cells, and modulation of cellular redox activity has been shown to influence self-interaction, aggregation, and cytotoxicity of TDP-43 –133. Oxies (MAM) , 138. MAes (MAM) –145. Tiglic Ca2+ –149. Incregation  2+ release and delayed buffering of cytosolic Ca2+ [2+ at the expense of mitochondrial Ca2+ storage [2+ from mitochondria involves TDP-43 phase transition remains an open question.Of note, induced pluripotent stem cell (iPSC)-derived motor neurons from patients carrying TDP-43 mutation display high glutamate-induced Calic Ca2+ , suggestlic Ca2+ . Furtherlic Ca2+ . These hlic Ca2+ , 151–155 storage . The TDP storage . In cell storage . The mitStability and dynamics of TDP-43 in motor neuronsMainly due to anatomical inaccessibility, TDP-43 dynamics have rarely been explored in vivo in mammalian motor neurons. Direct observation of TDP-43 in live motor neurons is, however, feasible in an optical-friendly vertebrate model, zebrafish , 24. We C9orf72-derived dipeptide transmission [Here, we enumerated different forms of TDP-43 granules in different intracellular locations and contexts. However, these various forms of TDP-43 are insufficient in providing a complete understanding of multifaceted TDP-43 dynamics, in healthy and diseased states. Therefore, it is necessary to explore further TDP-43 granules and their regulatory mechanisms that have not yet been discovered. Aberrant phase behavior of TDP-43 in RNP granules results in at least three reasonably conceivable consequences, differing in their gain-/loss-of-function nature: (1) generation of toxic TDP-43 oligomers or aggregates that further propagate via phase transition in a dominant fashion, (2) loss/reduction of proteins that are otherwise normally expressed, due to TDP-43-mediated regulation, and (3) generation of truncated translation products of abnormally spliced transcripts causing proteostatic cellular stress. These multiple phenotypes are likely to occur simultaneously rather than sequentially. Thus, an understanding of the upstream cellular events causing abnormal TDP-43 phase transition may be as important as the conventional gain-of-function versus loss-of-function dichotomy. An emerging figure, while largely omitted from this review, is the multisystem nature of ALS and FTLD, where TDP-43 pathology in degenerating neurons has been linked to extracellular factors, including inflammation, microglial toxicity, and intercellular smission –163. Stu


Graphene stands out as a versatile material with several uses in fields that range from electronics to biology. In particular, graphene has been proposed as an electrode in molecular electronics devices that are expected to be more stable and reproducible than typical ones based on metallic electrodes. In this work, we study by means of first principles, simulations and a tight-binding model the electronic and transport properties of graphene nanogaps with straight edges and different passivating atoms: Hydrogen or elements of the second row of the periodic table . We use the tight-binding model to reproduce the main ab-initio results and elucidate the physics behind the transport properties. We observe clear patterns that emerge in the conductance and the current as one moves from boron to fluoride. In particular, we find that the conductance decreases and the tunneling decaying factor increases from the former to the latter. We explain these trends in terms of the size of the atom and its onsite energy. We also find a similar pattern for the current, which is ohmic and smooth in general. However, when the size of the simulation cell is the smallest one along the direction perpendicular to the transport direction, we obtain highly non-linear behavior with negative differential resistance. This interesting and surprising behavior can be explained by taking into account the presence of Fano resonances and other interference effects, which emerge due to couplings to side atoms at the edges and other couplings across the gap. Such features enter the bias window as the bias increases and strongly affect the current, giving rise to the non-linear evolution. As a whole, these results can be used as a template to understand the transport properties of straight graphene nanogaps and similar systems and distinguish the presence of different elements in the junction. The presence of strong and directional covalent bonds in graphene makes this material especially reliable and suitable for many applications, including biological sensors , organicThe first step towards the design of graphene-based molecular electronic systems is the fabrication of a nanogap, i.e., a physical separation between two graphene layers of the order of nanometers or even smaller. This has already been achieved by some groups worldwide, which were able to create such gaps by using electroburning techniques ,12,13,14To properly characterize the electronic and transport properties of a nanogap it is necessary to determine the types of impurities that attach to the carbon atoms at the edges and passivate them. This is currently something difficult to achieve in an experiment, since the fabrication of nanogaps is still in its infancy. In particular, it is still not possible the control over the composition and morphology of the gaps, making it rather difficult to regulate and characterize the presence of impurities that attach to the graphene edges once the gap is created. The cleanliness of the gap can in principle be improved by using ultra-high vacuum chambers or certain atmospheres, but no certainty of the specific impurities that attach to different parts of the edges can be obtained.We show here that the transport characteristics of graphene nanogaps with straight edges can indeed be used to determine the type of impurities that attach to a given edge. Such characteristics depend strongly on the type of atom that passivates the edge and can be taken as a starting point to fully characterize its composition and configuration, opening the door to the development of nanogap-based electronic components ,17. We uThe article is structured as follows. In the next section, we explain the methods we used to calculate the electronic and transport properties of graphene nanogaps: Ab-initio simulations and tight-binding model. Next we present the main results and discuss them. We finish with the conclusions.y direction. Increasing the size of the unit cell or the number of k-points along y gave essentially the same results around the Fermi level, but dramatically changed the current in some cases, as we shall see. A vacuum region of 20 Å along the x direction was included to make sure the periodic images did not overlap along this direction. A total of 12 atoms and 10 k-points along the z direction were used in the simulation of the electrodes and 62 atoms were employed in the simulation of the scattering region .The electronic structure was calculated with density functional theory (DFT) , as implnctional . The grak-points along the transport direction to reproduce the bulk electronic structure. The Hamiltonian of the scattering region was computed in a simulation that included the gap, edges, and some bulk unit cells towards positive and negative z values to make sure the electronic structure converged to that of the bulk away from the gap. The effect of semi-infinite electrodes was then introduced as self-energy matrices that were computed from the electrodes Green functions. This assumed then that the electrodes are ideal semi-infinite graphene layers without additional contacts; notice, however, that the use of more realistic electrodes, which would include contacts between the graphene layers and metallic electrodes, could decrease the transmission and conductance [The transport calculations were carried out using the Gollum code , which gductance . The zermolecule . This meIn order to physically interpret the results and understand the trends behind the ab-initio transport results, a one-dimensional tight-binding model that can properly reproduce the transmission and current between graphene electrodes was also used . This mohis case  and onlyulations  because y direction, the atoms at the edge and near it can affect the transmission by inducing interference effects. These effects can also be simulated with the model by including additional couplings between the carbon and edge atoms [The absolute value of the transmission at the Fermi level depends on the strength of the ge atoms , i.e.,(z), to be zigzag. The structure can be seen in We consider armchair edges, which means the direction along which the electrodes are grown, and is the perpendicular transport direction  integrated around the Fermi level is shown in The transmission also changes sharply outside a window between −2.5 and 2.0 eV around the Fermi level. Below −2.5 eV, the transmission increases, while it decreases above 2.0 eV. These changes of the transmission can be explained by taking into account the presence of band-edges, due to the finite-width of the graphene layers, and the couplings between the edge atoms and graphene layer. From the PDOS, it can be seen that the pThe exponential decay of the conductance, obtained by calculating the transmission at the Fermi level as a function of the distance between the edge atoms on both sides of the gap, can be seen in y direction. As can be seen, when one unit cell is used to repeat the nanoribbon along the perpendicular direction, the current is ohmic at low voltages (lower than 0.25 eV) but then develops a rather non-linear behavior, with peaks and negative differential resistances (NDR). This behavior is not modified when k-points are used along y. The NDR features are in general rather sharp, with acute increases and decreases to almost zero values, something desirable for devices such as oscillators and amplifiers. Notice, however, that these NDR effects, which are prominent in the case of a coherent and ballistic transport regime, like the one assumed here, could be reduced when dissipative effects are taken into account  can also be explained by taking into account couplings across the gap of the impurity sites  . For insy and are responsible for the strongly non-linear behavior of the current in such a case. When two unit cells are used along y, however, the current becomes ohmic for the full voltage interval, up to 1.5 V or even higher, which is also in agreement with the simple tight-binding model without additional couplings. The same exact result is found when the number of unit cells is increased to three along y. This shows that the interference-related features disappear when the number of atoms along the perpendicular directions increases and seems to indicate that the non-linear behavior observed for one unit cell along y is a finite-size effect that comes from a particular design of the system with just one unit cell. We do not therefore exclude that such non-linear effects appear when truly finite-width nanoribbons are used, something that would need further investigation beyond the scope of this article. We can then conclude that it is necessary to use at least two unit cells to properly simulate the transport properties of armchair broken graphene sheets or wide ribbons.These interference features become then important in the case of just one graphene unit cell along y are compared in All ohmic currents calculated with two unit cells along By means of ab-initio simulations and a tight-binding model, we showed that the electronic and transport properties of graphene nanogaps with straight armchair edges depend substantially on the type of passivation of the edges. In particular, we obtained that such properties strongly depend on the the size and on-site energy of the atom that is used for the passivation. The size of the atom decreases the transmission and gives rise to smaller conductances and currents, i.e., the smaller the size of the atom, the smaller the conductance, and current. The on-site energy changes the slope of the transmission at the Fermi level and also affects the exponential decay. The smaller the on-site energy, the smaller the slope and bigger the y), the current turns out to be highly non-linear due to the presence of interference effects (Fano resonances and other interference-related features) that enter into the bias window at high voltages. The origin of these resonances can be traced back, with the help of the ab-initio model, to couplings between the carbon closest to the edge and side states (Fano states) that come from atoms located along the perpendicular direction. Other couplings between atoms across the gap can also give rise to additional interference features. When the size along the perpendicular direction is increased, however, such interference effects disappear and the current becomes ohmic. These results are useful, on one hand, to univocally determine the passivation of graphene nanogaps in current molecular electronics experiments with graphene electrodes and pave the way, on the other hand, for future studies of finite-size and interference effects in the transport properties of these systems.We also found that the


For all considered surface terminations, the binding energy of the MXene/graphene and MXene/AgNPs bilayers increases as compared with graphene/graphene and MXene/MXene bilayer structures. Such strong interlayer interactions are due to profound variations of electrostatic potential across the layers. Larger interlayer binding energies in MXene/graphene systems were obtained even in the presence of water molecules, indicating enhanced stability of such a hybrid system against delamination. We also studied the structural properties of Ti3C2X2 MXene  decorated with silver nanoclusters Agn (n ≤ 6). We found that regardless of surface functionalization, Ag nanoclusters were strongly adsorbed on the surface of MXene. In addition, Ag nanoparticles enhanced the binding energy between MXene layers. These findings can be useful in enhancing the structural properties of MXene membranes for water purification applications.The properties of two-dimensional (2D) layered membrane systems can be medullated by the stacking arrangement and the heterostructure composition of the membrane. This largely affects the performance and stability of such membranes. Here, we have used first-principle density functional theory calculations to conduct a comparative study of two heterostructural bilayer systems of the 2D-MXene (Ti MXenes, a growing family of layered low-dimensional transition metal carbides and nitrides, have attracted a lot of attention in the scientific community due to their unique chemical, physical and mechanical properties ,2. ElectMXenes have also emerged as high-flux, ultrathin, and size/charge selective nanofiltration membranes for water purification ,16,17. A3C2O2/MXene quantum dots/graphene heterostructures, causing changes to the electronic structure of QDs [MXene/graphene oxide (GO) hybrid systems have received a lot of interest due to their capacity to deliver enhanced mechanical properties , profound electrical conductivity, and very rich surface chemistries  ,21,22. Te of QDs .3 on the surface of MXene layers, which acts as a reducing agent) [Smaller water flux is one of the main issues preventing MXene membranes from being used in large-scale water purification applications. However, the water flux through MXene membranes can be increased significantly by increasing the interlayer spacing (see Ref.  for revig agent) . Dependig agent) . Rakhi eg agent) . Such MXg agent) .3C2F2, Ti3C2O2, and Ti3C2(OH)2), which are predominant functional groups of Ti3C2 MXene [In this work, we have conducted first-principle density functional theory (DFT) calculations to study the structural properties of the MXene/graphene bilayer system with and without the presence of water molecules. Special attention has been given to surface termination of MXene, which is known to be very important in determining both structural and electronic properties of the material ,37,38,39C2 MXene . We founn (n ≤ 6) absorbed on the surface of MXene layers using DFT calculations. We considered smaller nanoclusters (n ≤ 6), which preserve the planar arrangement of silver atoms. We found strong adsorption of Agn nanoparticles regardless of the surface termination of MXene. The smallest adsorption energies were obtained for fluorinated MXene. In addition, we found that metal clusters enhance the binding energy between MXene layers; this could be useful for increasing the stability of MXene-based membranes against delamination.Motivated by the recent experiments ,33, we a3C2 MXene with different surface functionalization, separately using DFT within the generalized gradient approximation of Perdew–Burke–Ernzerhof (PBE) to account for the exchange-correlation energy [−4 eV and 0.01 eV/Å, respectively. The hexagonal lattice parameter of graphene was 2.478 Å and the MXene samples had the following lattice parameters: 3.126 Å (Ti3C2F2), 3.094 Å (Ti3C2O2) and 3.142 Å (Ti3C2(OH)2). After optimizations, we constructed graphene/graphene, MXene/MXene, and MXene/graphene bilayer structures 2/graphene system 2/Ti3C2(OH)2 system has the largest binding energy. Interestingly, regardless of the surface terminations, MXene/graphene hybrid structures have stronger binding energy as compared to graphene/graphene and MXene/MXene systems, which are highlighted in Second, we optimized the structures in a more straightforward manner, i.e., by a direct force relaxation, considering van der Waals forces to accurately describe the interlayer interactions. The optimized structures for MXene/graphene bilayers are shown in 3C2O2/Ti3C2O2 system (dotted green curve in 3C2F2/Ti3C2F2 (dashed red curve in 3C2(OH)2/Ti3C2(OH)2 2/graphene systems as compared to the other samples 2/graphene sample. Then, the averaged induced charge on the carbon atoms was −0.0186|e|. Such redistribution of the charges resulted in pronounced electromagnetic potential variations across the MXene/graphene structures  charges method ,48, whicures see b.2OM+g+HE is the total energy of the total system, E2OH is the total energy of isolated water molecules, and ME/gE is the total energy of the isolated MXene/graphene bilayer. The calculated binding energies are shown in Finally, we studied the binding energies of MXene and graphene layers in the presence of water molecules at the interface between the layers. As a reference, we also studied the structural properties of graphene/graphene bilayer systems. We first conducted geometry optimizations starting from different initial positions and orientations of a single water molecule between the layers. The fully optimized structures are shown in 3 on the surface of MXene nanosheets (as it acts as a reducing agent) with an average size of 44 nm [n nanoclusters with n ≤ 6. The considered nanoparticles had planar structures. Interestingly, they preserved their planar geometry even after adsorption on the surface of MXene . We then conducted direct force relaxation, considering van der Waals forces to accurately describe the interlayer interactions. The lattice parameters that are perpendicular to the layers were equal to 100 Å during the geometry optimization. 6 nanocluster between the layers. For the fluorinated sample  increased the interlayer spacing considerably (compare columns two and three). For the fluorinated sample, the interlayer spacing increased only slightly (less than 1%) when the size of the nanocluster was increased. For the Ti3C2O2 sample, the interlayer spacing reduced significantly (~9.5%) when the cluster size was increased. This was due to the formation of covalent bonds between Ag and O atoms. A larger reduction in the interlayer spacing (~10%) was also obtained for Ti3C2(OH)2 MXene when the cluster size was increased  MXene decorated with Ag nanoclusters. We found that regardless of surface functionalization, the Ag nanoparticles were strongly adsorbed on the surface of MXene. This is despite non-covalent bonding between the silver and the surface atoms. The AgNPs also increased the binding energy of stacked MXene layers, which could be useful for enhancing the operational stability of MXene membranes for, e.g., water treatment applications.We have used DFT calculations to study the structural properties of graphene/MXene bilayer structures with different surface terminations of MXene. Regardless of the surface functional groups, stronger interlayer interactions were obtained in these hybrid systems as compared to graphene/graphene and MXene/MXene bilayers. Such enhanced interactions may have originated from the induced charges in the system, which resulted in strong electrostatic potential variations across the system. Larger binding energies were also obtained in the presence of water molecules in the system, indicating the possibility of enhancing the stability of such hybrid systems against delamination. We also studied the structural properties of Ti


Intermolecular hydrogen bonds are formed through the electrostatic attraction between the hydrogen nucleus on a strong polar bond and high electronegative atom with an unshared pair of electrons and a partial negative charge. It affects the physical and chemical properties of substances. Based on this, we presented a physical method to modulate intermolecular hydrogen bonds for not changing the physical–chemical properties of materials. The graphite and graphene are added into the glycerol, respectively, by being used as a viscosity reducer in this paper. The samples are characterized by Raman and 1H-nuclear magnetic resonance. Results show that intermolecular hydrogen bonds are adjusted by graphite or graphene. The rheology of glycerol is reduced to varying degrees. Transmission electron microscopes and computer simulation show that the spatial limiting action of graphite or graphene is the main cause of breaking the intermolecular hydrogen bond network structure. We hope this work reveals the potential interplay between nanomaterials and hydroxyl liquids, which will contribute to the field of solid–liquid coupling lubrication. So, the physical and chemical properties of materials are affected by intermolecular hydrogen bonding [Intermolecular hydrogen bond was presented by the IUPAC in 2004. It was defined  that the [et al.  studied  bonding –8.et al. [et al. [et al. [in situ powder metallurgy. The addition of graphite obviously improved the wear property of Al-alloy. Dou et al. [2 nanospheres coated with graphene had a larger specific surface, greater electrical conductivity and a longer cycle life. Chen et al. [et al. [et al. [Based on the above review of intermolecular hydrogen bonds, this paper tries to introduce some nanomaterials to investigate destroying the intermolecular hydrogen bond network structure and its effect on the physical–chemical properties of substances. Therefore, graphene and graphite, being a single graphite layer structure and a multi-graphite layer structure, respectively, are used. They are used in refractory, metallurgical casting, electric conduction, lubrication and other fields –12. Bag et al.  studied  [et al.  found th [et al.  providedu et al.  found thn et al.  reported [et al.  studied  [et al.  investigExcellent physicochemical properties of graphene and graphite gave them good solid lubricating property. In this paper, we try to add them to glycerol, respectively, and use their spatial limiting action after dispersion to destroy the hydrogen bond between glycerol molecules, while retaining the lubrication property of their solid lubricant. The ability of adjusting the intermolecular hydrogen bonds of glycerol after graphite and graphene addition was analysed, and the modulation mechanism was established. Meanwhile, the rheological properties of the mixture, after intermolecular hydrogen bonding was adjusted, were investigated.. 2m(glycerol)/m(graphite) and m(glycerol)/m(graphene) were denoted, respectively, by x and y .Graphite nanoparticles  were mixed with glycerol through ultrasound for a certain time at 25 ± 1°C. Then, the mixture was set for greater than 16 h. Glycerol mixed with graphene (The Six Element Inc.) was also prepared in the same way. The mixing mass ratio, respectively: 1H-nuclear magnetic resonance (NMR) was carried out using dimethyl sulfoxide-d6 as solvent and configuring 0.5 mol l−1 detection solution concentration. The rheology of the mixture was evaluated on Anton Paar Physica MCR301 under air-bearing torque of 0.002 µN m to 200 mN m and the detection temperature was 25 ± 1°C. The microscopic distribution of graphite and graphene was determined by JEM-2100 transmission electron microscopes (TEM). The computer simulation was performed at the same time.The mixed state of sample was analysed by radio mode of Horiba LabRAM HR, and the resolution was 2 µm. . 3The interaction between substances was reflected by a shift in the Raman spectrum peak. The strength of the chemical bonds was judged by the red and blue shift of the Raman spectrum peak. The Raman spectrum peak of infiltrated graphite and graphene is shown in −1. As shown in −1, respectively. After being infiltrated, the Raman spectrum peak of graphite and graphene had different degrees of displacement (red shift). This illustrated that graphite and graphene interacted with glycerol molecules, respectively, and the bonding ability of hydrogen bonds between glycerol molecules became weaker.The Raman spectrum peaks of the carbon materials were near 1350 and 1580 cm−1) of the graphite clearly shifted, while the Raman peak (approx. 1580 cm−1) of the graphene clearly shifted. Multi-layer structure and spheroidal structure of graphite resulted in more defect positions existing. Glycerol molecules were easier to interact with defect positions. However, single-layer structure of graphene had less defect positions. The Raman spectrum peak (approx. 1580 cm−1) of graphene had a more obvious red shift because of the charge attraction and the strong hydrophobicity of graphene. The intermolecular hydrogen bonds were modified by the interaction between graphite or graphene and glycerol molecules. The spatial confinement effect played a main role due to their strong hydrophobicity.From the size of the Raman spectrum peak displacement, the defect position Raman peak , the graphite was in a state of uniform dispersion in glycerol, and the ability to modulate the intermolecular hydrogen bond of glycerol was the strongest. With the decrease of adding amount, the modulation effect was weakened. Because of the large specific surface energy and the occurrence of small-scale agglomeration, when the amount of glycerol is reduced to x = 1000/1250/1500, its ability to modulate the intermolecular hydrogen bond of glycerol was basically the same. It showed that the thinning action of graphite was more dependent on its mass. Its action had been greatly weakened at x = 1000. Continuing to reduce its mass, the magnitude of viscosity reduction would not change significantly.The rheology curve of the mixtures (25°C) is shown in figure 3b, the thinning action of graphene was also obvious. With the decrease of the amount of graphene, the change law of viscosity of glycerol was different from that of graphite. It was easier for the surface of polar graphene to adsorb hydrocarbons. The more hydrocarbons adsorbed, the lower the surface energy, which reduced the agglomeration phenomenon. Compared with graphite, the number of monolayer graphene was much higher than that of graphite at the same amount. When the amount of graphene was the largest (y = 500), its aggregation in glycerol was serious, and its adsorption capacity for glycerol was weak. With the decrease of the amount of graphene, when the amount of graphene was reduced to y = 1000, the distribution of graphene in glycerol was more dispersed, and the adsorption of glycerol on each graphene reached saturation state. At this time, the graphene adsorbed by glycerol had lower specific surface energy. The aggregation phenomenon was reduced, and the ability to modulate the intermolecular hydrogen bond of glycerol was the strongest. However, with the decrease of the addition amount (y = 1250/1500), the modulation ability was weakened. This introduced that the thinning action of graphene had an optimal value, which could greatly reduce the viscosity of glycerol.As shown in figure 3a,b, graphite and graphene were evenly distributed in glycerol. The distribution and size of graphite in glycerol were different before and after shearing. Multi-lamellar structure of graphite was destroyed by the higher shear rate (4000–7000 r.p.m.). After shearing, the dispersion density of graphite in glycerol was clearly increased. Graphite was also destroyed in the process of ultrasonic mixing. It can be seen clearly that some smaller graphite was found in glycerol in figure 4a. Its space-limiting action became stronger. This damage increased the number of defect positions in the graphite, which explained why the Raman peak of graphite defect had shifted significantly.Usually, the physicochemical properties of graphite are not equal to that of graphene. The effect of multi-layer graphite on the viscosity of glycerol was more obvious than the effect of graphene in figure 4c. Its spatial confinement effect was not improved. Its thinning action on viscosity was mainly depending on its amount of addition. It was explained that the thinning ability of graphite on the viscosity of glycerol was stronger than that of graphene.Monolayer graphene was not destroyed by the higher shear rate in figure 4For more detailed description of the interaction between graphite and graphene with glycerol, a model of the adsorption of glycerol by graphite or graphene was established.The model of graphene was introduced from MS database. The serrated supercell structure of graphene was (6*6*1).et al. [et al. [figure 5a, there were no glycerol molecules around graphite according to the result of simulation. There were two glycerol molecules around graphene in figure 5b. This illustrated that graphite's multi-layer structure made its surface energy lower than that of monolayer graphene, and its hydrophobicity made it difficult to re-adsorb glycerol molecules on its surface. However, the space-limiting action of graphite and graphene in glycerol was still the main reason for the decrease of glycerol viscosity. Compared with monolayer graphene, graphite in glycerol could be destroyed at a high shear rate. Its multi-layer structure could be cut into even fewer layer or even single-layer structures. After shearing, the dispersion density of graphite was increased, which improved its space-limiting action. In addition, a small part of the newly formed monolayer graphene adsorbed glycerol molecules.The theory of partial seal transparency proposed by Shih et al.  and Li e [et al.  shows thAfter graphite/graphene with glycerol was mixed completely, their space-limiting action provided a special space for glycerol molecules. These special spaces transformed large glycerol clusters into small clusters, reducing the number of intermolecular hydrogen bonds. The newly formed small glycerol clusters were isolated by graphite, which prevented the formation of intermolecular hydrogen bonds between clusters. Moreover, a small amount of glycerol molecules were adsorbed on the monolayer graphene surface, which also reduced the number of glycerol molecules and the number of intermolecular hydrogen bonds in the bulk phase. This caused the viscosity of glycerol to be reduced.Modulation mechanism of intermolecular hydrogen bonds in this mixed system was simulated by the Castep model in MS software. The differential charge density simulation was based on Perdew–Burke–Ernzerhof (PBE) functional in generalized gradient approximation (GGA).As shown in 1H-NMR analysis.As shown in Therefore, the viscosity reduction mechanism of graphite and graphene in glycerol is shown in a, graphite was not surrounded by glycerol molecules due to its strong hydrophobicity. Multi-lamellar structure of graphite was destroyed in the process of ultrasonic and shear, which was in accordance with the results in figure 4b. The number of its layer was reduced, and even graphene was formed. The interaction between graphene and glycerol molecules is shown in figure 8b. Molecular clusters were broken by ultrasonic. At the same time, graphene was evenly dispersed in glycerol. A few glycerol molecules were absorbed on the surface of monolayer graphene and separated from each other by graphene. As shown in figure 8a, according to the simulation, only the monolayer graphene interacts with glycerol molecules, which reduced the size of the newly formed glycerol cluster. These new molecular clusters were isolated more thoroughly by a larger volume of multi-layer graphite through space confinement, which greatly reduced the probability of intermolecular hydrogen bonding between clusters. The number of intermolecular hydrogen bonds was greatly reduced, which resulted to reduce the viscosity of glycerol. This also made the viscosity-reducing effect of graphite stronger than that of graphene, which was in accordance with the results in As shown in figure 8. 4The intermolecular hydrogen bonds were adjusted by graphite and graphene, which resulted to decrease the viscosity of glycerol. Through experiment and computer simulation analyses, the hydrogen bond network structure of glycerol was destroyed, and the number of intermolecular hydrogen bonds was decreased. The different layered structure of graphite and graphene made their ability to adjust mechanism to intermolecular hydrogen bond and impact in the viscosity were different. The ability of graphite was affected by its additive amount and multi-layer structure, while that of graphene mainly depended on its additive amount. The effect of graphite (5.68%) is better than that of graphene (2.93%). In this paper, a new physical way was introduced to adjust the intermolecular hydrogen bond to reduce the viscosity of polyhydroxy liquid. At the same time, this work reveals the potential interplay between nanomaterials and hydroxyl liquids, which will contribute to the field of solid–liquid coupling lubrication.This paper found that graphite and graphene could be used as a solid nano-thinning agent with stable properties, and it was itself a good solid lubricant. But the side effect of them could destroy the integrity of the lubricating film on the surface of the friction pair and increase the friction coefficient. Its thinning effect was currently limited to liquids containing intermolecular hydrogen bonds. For the lubricating oil with a complex composition system, its function of thinning also remains to be proved.Click here for additional data file.


Furthermore, thermal energy management applications of the composites as phase change materials for solar‐thermal energy conversion and as thermal interface materials for electronic device cooling are demonstrated. The finding provides valuable guidance for designing high‐performance thermally conductive composites and raises their possibility for practical use in thermal energy storage and thermal management of electronics.Graphene is usually embedded into polymer matrices for the development of thermally conductive composites, preferably forming an interconnected and anisotropic framework. Currently, the directional self‐assembly of exfoliated graphene sheets is demonstrated to be the most effective way to synthesize anisotropic graphene frameworks. However, achieving a thermal conductivity enhancement (TCE) over 1500% with per 1 vol% graphene content in polymer matrices remains challenging, due to the high junction thermal resistance between the adjacent graphene sheets within the self‐assembled graphene framework. Here, a multiscale structural modulation strategy for obtaining highly ordered structure of graphene framework and simultaneously reducing the junction thermal resistance is demonstrated. The resultant anisotropic framework contributes to the polymer composites with a record‐high thermal conductivity of 56.8–62.4 W m −1 K−1(≈13.3 vol%), significantly outperforming previously reported results.The dual‐assembled graphene framework (DAGF), which combines a highly oriented graphene structure along the vertical direction and a low junction thermal resistance between the graphene building blocks, exhibits excellent performance in improving the thermal conductivity of polymers. The resultant composites have a record‐high thermal conductivity of 56.8–62.4 W m The accompanying interfacial heat transfer problem leads to an urgent demand for thermal interface materials (TIMs) with high thermal conductivity for removing excess thermal energy to guarantee the continuous and stable operation of the electronic devices. And in the field of thermal energy harvesting based on the phase‐change technology, the low intrinsic thermal conductivity (<0.5 W m−1 K−1) of the phase‐change materials (PCMs) is a long‐standing bottleneck, which greatly limited the thermal charging/discharging rate, thus causing a low heat‐utilization efficiency for diverse applications of PCMs, such as solar‐thermal energy conversion, thermal management of batteries, and thermal diodes. Therefore, addressing the thermal energy management issue by developing advanced thermally conductive materials has become necessary for the sustainable and stable development of the electronics and energy industries.In recent decades, along with the rapid development of electronic and energy technologies, a serious issue concerning thermal energy management has gradually emerged and is becoming of crucial importance for improving the performance of various devices.2, 32‐hybridized carbon atoms in a honeycomb lattice, exhibiting an extremely high thermal conductivity over 5000 W m−1 K−1. Such an excellent heat conduction performance has triggered considerable research interest in developing diverse graphene‐based materials to meet the ever‐increasing thermal energy management requirement, such as graphene papers as heat spreaders, graphene aerogels for solar thermal generation, and graphene/polymer composites. In particular, graphene/polymer composites, which were prepared by embedding graphene into polymer matrices, have been continuously spotlighted and implemented various applications in the electronics and energy field, due to the improved heat conductance, low density, and ease of processing. Currently, the direct dispersion of chemically exfoliated graphene sheets in polymer matrices by a solution or melt‐blending process is the most common way to prepare the composites. In this case, the critical issue is the high intrinsic interfacial thermal resistance between dispersed graphene sheets and polymer matrices, greatly limiting the thermal conductivity enhancement of the resultant composites.  Generally, to achieve an efficient thermal percolation pathway, a high graphene content up to 20–30 vol% in the polymer matrix is required, but nonetheless, the currently reported thermal conductivity enhancement (TCE = (κ − κm)/κm × 100%) is mostly lower than 3000%, resulting in a poor thermal conductivity of 4–6 W m−1 K−1, where κ and κm are the thermal conductivity of composites and polymer matrix, respectively. Accordingly, we can obtained that the specific TCE (TCE per 1 vol% filler addition) of the polymer matrices using the dispersed graphene as filler is almost less than 200%, inherently restricting the real thermally conductive applications of the corresponding composites.Graphene is a monolayer of covalently sp m−1 K−1.13 Suc And more effective thermal conductivity enhancement can be achieved by modulating the graphene framework to form a highly ordered and anisotropic structure instead of random arrangement. It can be attributed to the fact that the thermal conductivity of graphene is highly anisotropic, having an excellent capability to transfer heat along the basal plane, but poor along its cross‐plane direction. Current methods for the development of anisotropic graphene frameworks using graphene sheets, such as graphene oxide (GO), reduced GO (rGO), or graphite nanoplatelets (GNPs), can be typically divided into two approaches: the directional‐freezing of rGO aqueous dispersion and self‐assembly of GO liquid crystals. The former was usually carried out based on an ice‐templated assembly strategy, by which the graphene sheets can be spontaneously restacked on the edges of the unidirectional grown ice crystals to form an ordered arrangement.After incorporating with polymer matrices, typically, the thermal conductivity of the composites along the preferred direction can be up to 2.13 W m−1 K−1 with a graphene content of 0.92 vol%, corresponding to the specific TCE of 1338%. The anisotropic graphene framework can be also readily prepared utilizing the liquid crystal nature of GO, which arises from their intrinsic shape anisotropy and mutual electrostatic‐repulsion, leading to the spontaneous assembly of GO with a long‐range ordered structure in the aqueous dispersion. After air‐drying followed by a graphitization treatment at 2800 °C, Yu et al. embedded the as‐prepared anisotropic graphene framework into the epoxy, and obtained a currently record‐high thermal conductivity of 35.5 W m−1 K−1 for the graphene/polymer composites (19 vol%), giving a specific TCE up to 884% along the preferred direction. Although the above strategies have achieved a significant thermal conductivity improvement for polymers by incorporating the anisotropic graphene frameworks into the matrices, the thermal resistance between the adjacent graphene sheets within those frameworks is still fairly high. It can be attributed to that the graphene frameworks prepared through the commonly used spontaneous assembly method could just form an incompact contact between the adjacent graphene sheets with a low overlapping area of graphene‐graphene. Such an interfacial thermal resistance at the microscopic junction can ultimately contribute to the high total thermal resistance inside bulk composites, limiting the specific TCE mostly below about 1500% for the anisotropic graphene framework/polymer composites ever reported. Therefore, further interface optimization for reducing the junction thermal resistance between the adjacent graphene sheets within the anisotropic graphene framework is imperative to further improve the thermal conductivity of graphene‐based polymer composites.Recently, 3D graphene frameworks composed of interconnected graphene sheets have emerged as ideal reinforcements to develop thermally conductive polymer composites, due to the formation of the continuous thermal pathway between graphene fillers for rapid phonon transport.31 And−1 K−1 (≈13.3 vol%). This value achieved is equivalent to ≈325 times higher than that of neat epoxy, giving an ultrahigh specific TCE over 2400%. Additionally, given practical applications of thermal energy management, we further incorporated the as‐prepared DAGF with the polyethylene glycol (PEG) and the polydimethylsiloxane (PDMS), and the both demonstrated a superior performance using as PCMs, and TIMs, respectively. Our finding provides insight into the construction of graphene‐based thermally conductive composites, which may meet the ever‐increasing thermal energy management issue in electronics and energy fields.Herein, to address this issue, we proposed a dual‐assembly strategy with a multiscale structural modulation process to construct anisotropic graphene framework, which has not only a highly oriented arrangement of graphene along the vertical direction, but also an intimate contact of the adjacent graphene sheets with a low junction thermal resistance. As a result, the dual‐assembled graphene framework (DAGF) exhibited an excellent thermal conductivity enhancement effect on various polymer matrices, typically endowing the epoxy composites with a through‐plane thermal conductivity of 62.4 W m22.1Figure −1), the color of the film turned from yellow to black , and the sample size was mainly depended on the length of the film used in the process. For example, a large‐scaled graphene/PU with a diameter of ≈20 cm and a thickness of ≈8 cm can be obtained by continuously rolling up a 60 m long film. Finally, as shown in Figure k Figure ,f, due tk Figure . In Figu And the commonly used method was performed according to a “dipping and drying” process illustrated in Figure  However, it is difficult for conventional dipping method to achieve a large scale graphene framework while guaranteeing the homogeneity of the entire structure. It is mainly because when a large‐scale PU sponge was simply immersed into the graphene dispersion, the graphene sheets attached at the outer surface of the sponge would form a diffusion barrier layer to prevent the continuous penetration of dispersion toward the central region, finally leading to the nonuniform assembly of graphene sheets after drying. In contrast, the dual‐assembly strategy proposed in this study adopted the porous PU film with the thickness of 500 µm  as the starting template to immerse into the graphene dispersion, by which graphene sheets can diffuse from the normal direction of the film with a short diffusion distance of 250 µm. As illustrated in Figure 3), the diffusion distance of our dual‐assembly method (250 µm) is almost 16 times shorter than that of the conventional dipping method (4 cm), leading to the ease of uniformly attaching the graphene sheets on entire surface of the PU skeletons. The subsequent roll‐to‐roll step was carried out to postassemble the as‐prepared homogeneous graphene/PU film into a large‐scale graphene/PU monolith with uniformly distributed graphene sheets.Actually, the fabrication of interconnected graphene frameworks using porous PU sponge as the sacrifice template has been reported in previous works.52 And3) was investigated, with the three typical sampling regions illustrated in Figure 3) cut out from the three sampling regions in DAG/PU and CG/PU exhibits fundamentally different results. In Figure In order to intuitively demonstrate this point, the microscopic morphologies and graphene content at different regions from the edge to the center of the dual‐assembled graphene/PU (DAG/PU) monolith , where L and L0 are the length of the pristine and the stretched PU porous film, respectively. The detailed preparation process of the DAGFs can be found in Figure S4 (Supporting Information), and the microstructure change of them were presented in Figure L/L0 = 1) as the starting template (named as DAGF1) exhibits a fairly loose skeleton structure composed of quasi‐isotropic arrangement of graphene sheets  with the same original length, the resultant DAGF (DAGF5) presents an obviously lessened diameter of ≈15 mm  and through‐plane (κ⊥) thermal conductivities of 3.98 and 4.07 W m−1 K−1, respectively, indicating an approximately isotropic heat transfer enhancing effect of DAGF1. When the DAGFs with higher density were incorporated, both κ∥ and κ⊥ of DAGF/EPs present a significant improvement as a function of graphene content. Interestingly, we noticed that the κ∥ rises in an almost linear trend, whereas the increase of κ⊥ is approximately exponential, leading to a monotonical increase of the thermal conductivity anisotropy ratio (κ⊥/κ∥) versus the graphene content  can reach 24.8 and 62.4 W m−1 K−1, respectively, corresponding to a thermal conductivity anisotropy ratio (κ⊥/κ∥) of 2.52. The changing trend from approximately isotropic to anisotropic of thermal conductivity enhancement effect for the DAGFs on the epoxy as the increase of graphene content can be attributed to the structural change of the framework as discussed in Figure κ⊥ achieved of DAGF5/EP (62.4 W m−1 K−1) is over two orders‐of‐magnitude greater than that of polymer (0.2–0.4 W m−1 K−1), and outperforms that of many metals and ceramics.Based on the characteristic interconnected structure composed of highly ordered graphene sheets, the DAGF is expected to be a promising candidate as thermally conductive fillers embedded into polymer matrices to develop composites with improved thermal conductivity for highly efficient thermal energy management. To confirm this, the DAGF/epoxy (EP) composites were prepared, and the contribution of the DAGFs on the heat transfer capability of epoxy was studied. Epoxy was chosen because it is not only a widely utilized thermal management material in the electronic packaging field, but also the most commonly used polymer matrix for evaluating the heat transfer enhancing effect of the applied fillers in academia. In κ⊥ of our composite. In Figure 3 were placed on a ceramic heater (60 W) for heating them at the same time from room temperature. To precisely measure the time‐dependent surface temperature of different materials using a commercial infrared (IR) camera, the top surface of the two samples was coated by a thin graphite layer (≈5 µm) to ensure the same infrared emittance. As the results shown in Figure Furthermore, we carried out a comparative test on through‐plane heat transfer capacity between DAGF5/EP and tin (Sn) for directly demonstrating the ultrahigh Figure  The κ∥ enhancement of DAGF/EPs presents a relatively consistent rising pattern as compared to the general trends of the currently reported results. However, note that the TCE of κ⊥ shows an accelerated growth rate versus the graphene content, and begins to significantly outperform that of the latest reports when the graphene content exceeds about 10 vol%. To understand such an extraordinary κ⊥ enhancement of DAGF/EPs, our experimental κ⊥ was matched using a heat conduction model according to the metal foam theory, which takes the foam skeleton as the research object, and combines the κskeleton and the κEP through a rule of mixturesκEP is the thermal conductivity of the epoxy matrix; κskeleton is the solid thermal conductivity of an individual graphene skeleton of DAGFs; f is the volume fraction of graphene; θ is the angle between the graphene skeleton and the direction of heat transfer, and the angle bracket indicates the average value over all graphene skeleton. The detailed calculation and analysis can be seen in Section S2 (Supporting Information). As the results shown in Figure κskeleton was taken as 560 W m−1 K−1, the predicted results of Equation (f < 7.2 vol%) of our experimental data, whereas underestimating the κ⊥ of the last two points, which can be matched by assigning a higher κskeleton of 770 and 950 W m−1 K−1 for Equation  and overlapping area (S) of adjacent graphene sheets can be estimated using the Equations κ⊥ of tκ⊥ is the through‐plane thermal conductivity of the composites versus the volume fraction (f); κEP is the thermal conductivity of the epoxy matrix; κ0 is the pre‐exponential factor ratio related to the contribution of graphene sheets; fc is the critical volume fraction of graphene sheets, and τ is a conductivity exponent; L is the plate size of the graphene sheets (≈5.4 µm); Rint is the interfacial thermal resistance of the overlapped graphene sheets based on the van der Waals (vdW) interaction, and therefore the Rint for the two cases is the same, ideally, at the order of magnitude level of 10−9 K m2 W−1. Based on the experimental κ⊥ of DAGF1/EP and DAGF5/EP, as well as the corresponding change trend predicted using the Equation . According to Equation (−14 m2) is ≈2.1 times as high as that of DAGF1/EP (4.57 × 10−14 m2). Moreover, based on the result of nonequilibrium molecular dynamics (NEMD) simulation . The detailed calculation and analysis of the Foygel model and the NEMD simulation can be found in Section S3 and Figure S9 (Supporting Information). And the results confirm the superior κskeleton of an individual graphene skeleton for the higher‐density DAGFs, and provide fundamental evidence to explain the extraordinary κ⊥ enhancement of DAGF/EP with the increase of the graphene content. As a result, the κ⊥ enhancement of the corresponding DAGF5/EP can be as high as 325 times that of neat epoxy at the graphene content of 13.3 vol%. To the best of our knowledge, this κ⊥ enhancement achieved is the highest value ever reported for graphene/polymer composites with a similar level of graphene addition  resulting in a limited speed for the energy conversion is an everlasting bottleneck, which has caused a low efficiency for energy charging/discharging. Numerous studies have indicated that the incorporation of PCMs with 3D graphene frameworks is a feasible solution to develop highly thermally conductive PCM‐based composites for solving this problem. Here, based on the excellent performance of our DAGFs in enhancing the thermal conductivity of the polymer matrix, we combined the PEG  with the as‐prepared DAGF5 using a conventional infiltration method  of DAGF5/PEG is 139.7 J g−1, which is about 78% that of neat PEG (179.2 J g−1), attributing that the additional graphene component did not undergo a phase change. Besides, as shown in Figure Tonset) of DAGF5/PEG is approximately the same as that of neat PEG, when the DSC heating rate was changed from 10 to 90 °C min−1, suggesting that the embedding of graphene into PEG does not effect on its normal solid–liquid phase transition. Interestingly, in contrast to the Tonset, the Tend (end melting temperature) of DAGF5/PEG (73.4 °C) presents a significant decrease of about 10 °C compared to that of PEG (83.6 °C) at the heating rate of 10 °C min−1, and this temperature difference (ΔTend) is further raised to 43 °C, as the heating rate up to 90 °C min−1. We proposed that the faster phase‐change speed of DAGF5/PEG compared to that of PEG can be attributed to its superior thermal conductivity , substantially deriving from the highly ordered graphene sheets acted as the continuous heat channels within the PEG matrix.The differential scanning calorimetry (DSC) curves Figure  indicatee=κρΔHm) can be used to evaluate the capability to exchange thermal energy with the surroundings, where κ, ρ, and ΔHm are the thermal conductivity, density, and phase change enthalpy of the PCMs, respectively. As shown in Figure −1 K−1, our DAGF/PEG exhibit a record‐high thermal effusivity as compared to the currently reported carbon‐based phase‐change composites.Accordingly, a finite element modeling using a commercial computational fluid dynamics software (ANSYS) is implemented to simulate the transient thermal response of neat PEG and DAGF5/PEG, respectively, for mimicking the DSC heating process. The simulation model of the two samples was shown in Figure L/S ≈ 36: 64) after 500 min of illumination, as shown in the IR images in the inset of Figure −1 K−1), which prevents the rapid spreading of absorbed heat energy from the top surface into the interior of the sample, showing a large temperature gradient of 8.9 °C cm−1 along the vertical direction the sample. In contrast to the neat PEG, after being illuminated for 55 min, the phase transition of the entire DAGF5/PEG can accomplish with a steady‐state temperature of 76.2 °C (Node 3) and 73.4 °C (Node 4) at the top and the bottom position, respectively. And at the steady‐state of the charging process, the temperature gradient through the DAGF5/PEG is only 1.4 °C cm−1, demonstrating a much faster heat transfer efficiency, due to the efficient heat propagation along the interconnected graphene skeleton. During the heat discharging process without the light source, the temperature of the DAGF5/PEG is always higher than that of the PEG. Moreover, different from the gradual decrease of the temperature of the PEG, the DAGF5/PEG presents a temperature plateau (46.5–48.5 °C) between 530 and 550 min, suggesting that the heat energy release for DAGF5/PEG can be maintained at a relatively high‐quality level in a wide range of cooling time. Besides, compared to the large temperature difference between the top and bottom of PEG, the temperature gradient through the DAGF/PEG is almost zero during the entire heat discharging process, indicating the superior heat discharging efficiency of DAGF5/PEG compared to that of neat PEG. Not only the excellent light‐to‐thermal energy conversion capability, the DAGF5/PEG also exhibits good shape stability and no leakage of PEG during the during the charging/discharging process . This result demonstrates the promising possibility to achieve highly efficient thermal energy storages by the incorporation of the thermally conductive DAGFs with the conventional phase change materials.Given the practical application of thermal energy storage and management, DAGF5/PEG could be employed as a solar‐thermal energy conversion materials, which work by the transformation of the absorbed solar energy at the surface into the thermal energy through a phase transition of the applied PCMs. The solar‐thermal conversion performance test for neat PEG and DAGF5/PEG are illustrated in Figure 2.4κ⊥ of the polymer matrix can also endow the composites with considerable potential for use as high‐performance TIMs. TIMs are applied to bridge the heat‐generating electronic components (heater) and the heat sink for dissipating excess heat along the vertical direction, thus expecting to have a high κ⊥ for maximizing the heat energy transfer efficiency, as schematically illustrated in Figure −1 K−1) and obtain the DAGF5/PDMS composite. For TIM application, the sample was cut into a thin pad with good bendability and compressibility , which is much higher than that of the state‐of‐the‐art commercial TIMs (10–35 W m−1 K−1).In addition to as thermally conductive fillers incorporated with PCMs for the energy harvesting applications, the excellent capability of our DAGFs in improving the y Figure  of the c−1 K−1, Fujipoly XR‐m, Japan) and a vertically aligned carbon fiber‐based thermal pad . As far as we know, both are state‐of‐the‐art commercial products with the highest thermal conductivity in their respective fields. A water cooling system was employed to keep the heat sink temperature constant at 25 °C during the test, and the real‐time temperature evolution of the heater (Theater) was monitored using a calibrated thermocouple. As the results shown in Figure −2) and the heat sink with TIMs. Noticeably, the cooling performance of DAGF5/PDMS with the heater temperature drop of 57 °C is substantially greater than that of XR‐m (39 °C) and EX20000C7 (46 °C) thermal pads. In Figure ) for the three TIMs can be calculated with the value of 1.76, 1.32, and 1.09 K cm2 W−1, assigned to the DAGF5/PDMS, EX20000C7, and XR‐m thermal pads, respectively. This result indicates that the system cooling efficiency using DAGF/PDMS as TIM achieves 61% and 33% enhancement compared to that of the XR‐m and EX20000C7 thermal pads, respectively.To study the practical cooling performance of the as‐prepared DAGF5/PDMS, a TIM performance test apparatus was built to simulate the actual heat transfer behavior of the electronic devices. In Figure e fields.79 A w−2 , and the effective thermal conductivity (κeff) of three TIMs was calculated based on the steady‐state heater temperature shown in Figure κeff value of DAGF5/PDMS reaches up to 18.6 W m−1 K−1, which is ≈2.2 times and ≈1.7 times as high as that of XR‐m (8.5 W m−1 K−1) and EX20000C7 (10.9 W m−1 K−1) thermal pads, respectively. Besides, based on the equation: Rc = BLT/κeff − BLT/κTIM, our DAGF5/PDMS has a lower thermal contact resistance (two sides) of 28 K mm2 W−1 compared to that of state‐of‐the‐art commercial thermal pads . The details can be seen in Table S5 (Supporting Information), where the BLT and the κTIM are the thickness in the packaging state and the through‐plane thermal conductivity of the applied TIMs, respectively. The lower contact thermal resistance of our DAGF5/PDMS can be attributed to its lower filler volume fraction (≈13.3 vol%) compared to that of the commercial thermal pads (50–70 vol%), leading to more soft matrix material directly in contact with the rough surface of the heater/heat sink with a better gap‐filling. As a result, combining the dramatically higher through‐plane thermal conductivity and the relatively lower contact thermal resistance, the simulated temperature profiles demonstrate the excellent heat dissipation capability of our DAGF5/PDMS for TIM application, as shown in Figure A commercial flow solver (IcePak) was then adopted for in‐depth analysis of our test system at a power density of 50 W cm−2. The measurement results in Figure −2 for 10 days in a real environment, and the temperature of the heater (Theater) and the ambient (Tambient) were captured using a thermocouple. The Theater showed a fluctuated variation over time, attributing to the ever‐changing Tambient, which was vulnerable to the large temperature difference between day and night, as well as the changes in the weather during the test period. Despite that, the temperature difference between the heater and the ambient (Theater – Tambient) remains almost unchanged during the whole period, indicating an excellent long‐term durability of DAGF5/PDMS as TIM. The comparative TIM performance test suggests that by incorporating DAGF5 with soft PDMS matrix, the obtained composites can be an up‐and‐coming candidate to replace the state‐of‐the‐art commercial thermal pad for dealing with the ever‐increasing thermal energy management issue of next‐generation advanced electronic devices.Additionally, a cyclic thermal shock test using DAGF5/PDMS as TIM was carried out by alternatively switching the power density of the heater between 5 and 50 W cm3κ⊥ of epoxy by ≈325 times (62.4 W m−1 K−1). To the best of our knowledge, this value achieved is the currently highest value for the graphene framework/polymer composite, and gives an ultrahigh specific TCE over 2400%. Additionally, given the practical applications thermal energy management, the preparation and the performance study of the DAGF5/PEG and DAGF5/PDMS composites were simultaneously reported in this work. We demonstrated that the DAGF5/PEG as PCMs achieved an increased heat transfer rate by ≈200 times that the neat PEG in the solar–thermal energy conversion, and the DAGF5/PDMS performed excellently in application as TIM with the cooling performance‐enhancing by 33–61% compared to that of state‐of‐the‐art commercial TIMs. The present work provides insights into the construction of graphene‐based thermally conductive composites, which may satisfy the thermal energy management requirements arriving from the rapid developments of electronic and energy technologies. Besides, compared to the various techniques ever reported, such as CVD  growth of graphene framework or CNT (carbon nanotube) sponge, the proposed dual‐assembly strategy, involving a rolling process and high‐temperature annealing, is relatively more straightforward and cost‐effective. It can significantly raise the possibility for the practical application of the as‐prepared thermally conductive graphene‐based composites. Furthermore, this method is not limited to graphene sheets but can also be applied toward the assembly and design of the other 2D nanomaterials  into a macroscopic configuration for more possible practical application.In summary, we developed a highly ordered graphene framework with an intimate contact of its internal adjacent graphene sheets to achieve a superior specific TCE for polymer composites by a dual‐assembly strategy. We demonstrated that the dual‐assembly strategy with a continuous stress‐induced orientation process can not only manipulate the arrangement of the graphene skeleton leading to the formation of highly ordered architecture, but also further reduce the junction thermal resistance between the adjacent graphene sheets by enhancing the overlapping area. As a result, the as‐prepared DAGF5 exhibited superior performance in improving the thermal conductivity of polymers, dramatically enhancing the 4Graphene sheets with the average lateral size of 5.4 µm and thickness of 10.6 nm were prepared through the intercalation and exfoliation of graphite. Porous PU film was obtained from Suzhou Shutao Medical Supplies Co., Ltd. (China). The epoxy matrix (6105) and the hardener  were purchased from DOW Chemicals (USA) and Shanghai Li Yi Science & Technology Development Co., Ltd. (China), respectively. The Neodymium(III) acetylacetonate trihydrate (Nd(III)acac) was purchased from Aldrich Chemicals. PEG with the numerical‐molecular average weight (Mn) of 4000 was purchased from Aladdin Reagent Co., Ltd. PDMS (Sylgard 184) and the hardener were purchased from Dow Corning Co., Ltd. . Ethanol was purchased from Sinopharm Chemical Reagent Co., Ltd. (China). All chemicals were of analytical reagent grade and used without further purification. The Fujipoly XR‐m and the Dexerials EX20000C7 thermal pads were purchased from Fujipoly Trading (Shenzhen) Co., Ltd and Dexerials Corporation (Japan), respectively.−1) to assemble graphene sheets on the surface of PU skeleton, followed by a continuous roll‐to‐roll step to roll up the film into a cylinder (graphene/PU monolith). The film was kept in a tensile state in the roll‐to‐roll process and the stretch ratio was strictly controlled and ranged from 100% to 340% . The detailed preparation process of graphene/PU monolith using the stretched PU porous film as the starting template can be found in Figure S4 (Supporting Information). Then, as‐prepared graphene/PU monolith was thermally annealed at 800 °C (1 h) in vacuum for the removal of the PU, followed by the graphitization at 2850 °C (1 h) in an argon atmosphere to obtain a series of DAGF (DAGF1–5).Graphene/PU monolith was prepared using a dual‐assembly strategy, by which porous PU film was continuously immersed in graphene/ethanol solution acac was added into epoxy precursor and stirred for 2 h (80 °C) to prepare a homogeneous solution, which was subsequently mixed with a curing agent (MHHPA) at the weight ratio of 100:95 to obtain the epoxy prepolymer. A series of DAGF (DAGF1– 5) was then immersed into the prepolymer for 1 h under vacuum to infiltrate epoxy and remove the air bubbles. Finally, procedural thermal curing of 135 °C (2 h) and 165 °C (14 h) was carried out to obtain the DAGF/EP composites (DAGF1/EP–DAGF5/EP).The DAGF5/PEG composites were fabricated by the infiltration of PEG into porous DAGF5 frameworks with the assistance of a vacuum. The raw PEG powder was first heated to 90 °C to obtain a fully melted PEG with good fluidity. Then, the DAGF5 frameworks were immersed into the melted PEG, and moved the both in a vacuum oven at 90 °C for 5 h to fully infiltrate the PEG and remove the air bubbles. Finally, the samples were cooled at room temperature to obtain the DAGF5/PEG composites. The DAGF5/PEG composites were prepared by the immersion of the DAGF5 frameworks into the mixture of PDMS prepolymer and curing agent with the weight ratio of 50:1. Then the samples were placed in a vacuum oven more than 4 h (room temperature) to remove the air bubbles, followed by curing at 80 °C for 5 h to obtain the DAGF5/PDMS composites.−1. The DSC heating and cooling scan of the PCMs was taken by a PYRIS Diamond system . The thermal diffusivities (α) of the sample were measured using LFA 467 MicroFlash system . The thermal conductivity (κ) can be calculated by the equation: κ = α × ρ × Cp, where ρ is the measured average density determined by the water displacement method and Cp is the specific heat capacity of the sample evaluated by using a DSC . The infrared (IR) photos were captured by using an infrared camera . The compression modulus of DAGF/PDMS was tested using a UTM . The loading rate was controlled as 0.5 mm min−1. The compressive modulus of the samples was obtained by calculating the average value of the tangent modulus (E = dσ/dε) in the range of 5–30% strain, where σ is the compressive stress and ε is the corresponding strain. The shape stability of DAGF/PEG was indirectly evaluated by testing the retention rate by using a stress‐controlled rheometer . During the measurement, the sample was applied a constant pressure of 1 N and heated from 30 to 100 °C (heating rate of 2 °C min−1) in a N2 atmosphere.Raman spectra were recorded using a Reflex Raman System  employing a laser wavelength of 532 nm. The sample morphologies were examined with field emission scanning electron microscopy . TGA was performed using the TGA 209 F3  system to confirm the weight percent of graphene in the polymer matrix. The measurements were carried out under nitrogen in the range from 30 to 800 °C at the heating rate of 10 °C minMicrosoft Excel and OriginPro  were used for the statistical analysis of the data presented in this work. All thermal conductivity data were presented as mean ± SD (standard deviation) and the sample size to be tested was listed in Section S1 (Supporting Information). The sample size of the DAGF‐based PCMs and TIMs was detailed descripted in the corresponding Discussion.The authors declare no conflict of interest.Supporting InformationClick here for additional data file.