In the present study, well-designed nanohybrids are used to act as effective dual-function adsorbents for removing both anions and heavy metals from natural water, at the same time. In this trend, Zn-Al LDHs and graphene oxide are applied to build up building blocks to produce a series of nanohybrids. These nanohybrids were characterized by X-ray diffraction, thermal analyses, Fourier transform infrared spectroscopy, Raman spectroscopy, and scanning and transmission electron microscopy. These techniques confirmed that the prepared nanohybrids contained nanolayered structures with three–dimensional porous systems. These porous systems were identified by the nitrogen adsorption-desorption isotherms and water purification experiments. The obtained results indicated that these nanohybrids included suitable structures to act as dual function materials. The first function was achieved by removing more than 80% of both cadmium and lead from the natural water. The second function was accomplished by eliminating of 100% of hydrogen phosphate and bromide anions alongside with 80%–91% of sulfate, chloride, and fluoride anions. To conclude, these well-designed nanohybrids convert two-dimensional nanolayered structures to three-dimensional porous networks to work as dual-function materials for removing of heavy metals and different kinds of anions naturally found in the fresh tap water sample with no parameters optimization.  It is well known that the quality of drinking water plays an important role in public health of a community. Therefore, the chemical composition of surface water and groundwater, as sources of fresh water supply, is considered a critical issue for water quality . One of Recently, many beneficial processes such as electrocoagulation, sorption and electrochemical separation have been employed to remove several types of pollutants from aqueous mediums . HoweverTherefore, the current study focuses on designing dual-function materials to be effective for removing both anions and heavy metals at the same time from real water. These materials were built by combining two building blocks together into well-designed nanostructures. Layered double hydroxide (LDH) and graphene sheets are suitable as building blocks for producing the dual-function nanostructures.1−xMIIIx(OH)2]x+(A)n−x/n·mH2O, where MII and MIII are di-valent and tri-valent cations; respectively and An− is the interlayered anion [In one hand, LDHs are inorganic layered materials with a general formula of [MIIed anion ,13. In ted anion . LDHs maed anion . On the ed anion . The comGoh et al.  investigTherefore, the current study aims to prepare a set of dual-function nanohybrids to remove different kinds of inorganic anions and some heavy metals from natural water of the national network of Eastern providence of Saudi Arabia. These nanohybrids are based on the nanolayered structures of Zn-Al LDHs and graphene oxide. This target can be completed through marriage with two building blocks together into well-designed nanostructures. Certainly, layered double hydroxide (LDH) and graphene sheets are suitable for building blocks to produce the dual-function nanohybrids. In this trend, Zn-Al LDHs are prepared and doped by the prepared graphene oxide to build new micro-porous and meso-porous structures through growths of the nanolayers of LDHs on the nanosheets of graphene oxide. In order to maximize the efficiency of these nanohybrids, different percentages of graphene oxide are used to obtain the optimum percentage of graphene oxide for improving the texture of Zn-Al LDHs. Surface properties of the prepared nanohybrids are measured and compared with the pure Zn-Al LDHs. The prepared nanohybrids are also characterized by X-ray diffraction, Fourier Transform Infrared Spectroscopy and Raman Spectroscopy. In addition, a morphological study is investigated through scanning electron microscopy and transmission electron microscopy. The prepared nanohybrids are applied to remove monovalent anions such as: fluoride, chloride, and bromide alongside with di-valent and tri-valent anions such as sulfate and hydrogen phosphate from the natural water. In order to indicate the dual-function effect of the prepared nanohybrids, these materials are applied to remove the heavy metals (cadmium and lead) from the same water sample.Hence, based to the best knowledge of the authors, the current work would count as a pioneer study for applying nanohybrids as a dual-function adsorbent for removing different kinds of anions as well as cations such as heavy metals in real fresh water.The nanosheets of graphene were prepared by the electrochemical cell as shown in 3)2∙6H2O with 0.02 mol of aluminum nitrate hexahydrate Al(NO3)3∙9H2O in the presence of 0.05 mol of urea CO(NH2)2. This reaction was achieved in the presence of 0.11 g of the oxidized form of graphene suspended in 750 mL of deionized water. The reaction occurred at 80 °C in the water bath. The grey-white product was precipitated and washed several times by deionized water after 24 h.In order to avoid hydrophobic behavior of the graphene sheets, they were oxidized through the reaction with hydrogen peroxide in ultrasonic bath. A total of 0.6 g of graphene was suspended in 500 mL of water and 100 mL of hydrogen peroxide (30%) for 2 h. The nanohybrid (NH1) was prepared by the reaction of 0.05 mol of zinc nitrate hexahydrate Zn. Transmission Electron Microscopy  was carried out at room temperature with an acceleration voltage of 200 kV. Raman spectra measurements were performed using LabRAM HR Evolution, Horiba-Jobin Yvon Technology, with laser 633 ULF. The grating groove density was 300 grooves/mm. The methods of Brunauer–Emmett–Teller (BET) and Barrett–Joyner–Halenda (BJH) were adopted to determine the material surface area, pore volume, and pore size distribution. Inductively coupled plasma emission spectroscopy  and ion chromatography  were employed to analyze the concentration of ions in solutions.The crystalline structures of Zn-Al LDH and the new nanocomposites were confirmed by X-ray diffraction ) by a scan rate of 0.5°/min. The functional groups were recorded through Fourier Transform Infrared Spectroscopy (FTIR) over the wave number range 400–4000 cmi and Cf (mg/L) is the initial and final concentrations of ions, respectively.The removal efficiency RE (%) of the samples was investigated at room temperature. Typically, a weight (g) of the sample was stirred in a volume V (L) of fresh tap water  at pH 6 up to 5 h to prepare constant concentrations W/V (10 g/L) of aqueous solutions. In order to study the effect of the adsorbent amount, two other concentrations (20 g/L and 30 g/L) were also used. Before achieving equilibrium, the concentrations of ions in solution were tested every hour. After equilibrium, the suspension was separated by centrifugation, and then the residual concentrations of cations and anions were determined by inductively coupled plasma mission spectroscopy (ICPE) and ion chromatography (IC) as shown in The crystalline structures of the prepared materials were determined by the powder X-ray diffraction technique as shown in The nanolayered structure of the prepared Zn-Al LDH was confirmed by the X-ray diffraction pattern shown in The X-ray diffraction patterns of the prepared nanohybrids NH1, NH2 and NH3 are displayed in By decreasing the content of graphene oxide to 2.5%, Due to continuous reduction of the graphene oxide content to 1.3%, three series of layered structures were observed in the X-ray diffraction of the nanohybrid NH3 as shown in The current data represented that graphene oxide played an important role for building up the nanolayered structure of the prepared nanohybrids. The nanohybrids NH1 and NH2 obtained one kind of nanolayered structure while three kinds of nanolayered structures were observed for the nanohybrid NH3. In order to explain this finding, we will discuss the dispersion of the nanosheets of graphene oxide during the growth process of LDH nanolayers. In the case of the nanohybrids NH1 and NH2, the high percentages of graphene oxide exist as groups when building up their nanolayered structures because of their aggregation behavior. It caused formation of one kind of combination between LDH layers with the nanosheets of graphene oxide. For the nanohybrid NH3, the low percentage of graphene oxide gave high dispersion in the medium. Therefore, their nanosheets exist as a single, few and/or groups. During growth of the nanolayers of LDH, three different kinds of interactions occurred with the nanosheets of graphene oxide while producing three different kinds of nanolayered structures. This description was confirmed by analyzing TEM images and surface measurement (will be discussed later).Another effect was observed for graphene oxide on the crystal size of the LDH layers because of the considerable broadened diffraction peaks of the prepared nanohybrids. Thus, the Debye–Scherer equation was applied to calculate the crystals size of the nanohybrids NH1, NH2 and NH3. According to the peaks of the planes 003, 006 and 009, the mean crystal size of the nanohybrid NH1 was calculated to be 17.0 nm. In case of both NH2 and NH3, they became 26.0 nm and 15.0 nm, respectively. However, the calculations of the pure Zn-Al LDHs showed that its crystal size was 74.40 nm. It highlighted that the presence of graphene sheets played vital role for production platelets of LDHs in the nano scale, which is in agreement with our previous studies for producing nanolayers of LDHs using carbon nanotubes .It is known that graphene consists of a two-dimensional structure. Therefore, SEM images of the prepared graphene exhibited plate-like morphology as shown in SEM images in By decreasing the content of graphene oxide, SEM images of the nanohybrid NH2 revealed very small aggregates looking like nanoflowers as shown in Energy-dispersive X-ray spectrometry (EDX) analysis indicated local data of the different elements in the outermost layers of the platelet of the nanohybrids. Zinc, aluminum, carbon and oxygen were clearly identified in the nanohybrids NH1 and NH3. It is known that graphene is a single layer of graphite. Consequently, TEM images of the prepared graphene revealed individual and multi-layers in the nano scale as shown in Due to the combination of graphene oxide with LDH, new structures of nanohybrids were released as presented in −1 reference to the structural defects and disorder graphitic carbon while, the second band recorded at 1600 cm−1 represented order graphitic carbon by confirming the existence of the hybrid sp2 atoms of carbon in graphene layers. By forming the nanohybrids based on the prepared graphene oxide, the main bands of graphene oxide were slightly shifted to lower wavenumbers for the nanohybrids NH1, NH2 and NH3. In case of the nanohybrid NH1, −1 and 1586 cm−1 by considering the presence of graphene sheets in the matrix of the layered structure of NH1. The observed shift for these bands indicates the strong interaction between the sheets of graphene oxide and the nanolayers of the LDH. New bands were observed at 1043 cm−1 and 516 cm−1. The new bands were due to M–O–C and M–O–M  [Raman spectroscopy is considered a well-known technique for exploring graphitic materials. l atoms) . It indil atoms) . The Fourier Transform infrared (FT-IR) spectroscopy was applied to compare between the function groups of the prepared LDH and the nanohybrids. The concentrations of some selected anions and heavy metals of interest for water quality were analyzed in a fresh sample of tap water from the domestic water network. The results of the analyzed sample were reported in −, HPO42−, F−, Cl− and SO42− as well as two heavy metals, (Cd and Pb). The behavior of these different anions to be adsorbed to the different materials prepared is illustrated in − and HPO42−. The removal efficiency (RE) of 100% was achieved with all types of nanohybrids NH1, NH2 and NH3. In contrast, adsorption by the parent structures of LDH was reported to be approximately 5% and 70% to HPO42− and Br−; respectively. The second attitude was noticed for both SO42− and Cl− ions. Their adsorption was poor (20%–30%) by the parent structure LDH, but gradually improved relative to increasing the amount of GO in structures prepared as well as increasing the W/V factor. However, the maximum RE% for SO42− and Cl− ions was calculated as ~80% for NH1 (W/V = 30 g/L). The obtained results by the current study showed enlargement in the removal percentage of the mentioned anions in comparison to the results concluded by Hatami et al. [The five different materials, previously mentioned, were examined for the water purification experiment GO, LDH, NH3, NH2, and NH1(a) with W/V = 10 g/L, while NH1(b) and NH1(c) were tested with W/V= 20 g/L and 30 g/L; respectively. Additionally, five anions were tested in a water sample for the following adsorption experiments: Bri et al.  who testLastly, the RE% for fluoride was 70% and 78% for GO and ZnAl-LDH (pristine structures) respectively, while it achieved up to 91% by the NH1 structure (W/V = 30 g/L). This result is higher than what was reported by Elhalil et al.  who mentHence, one can conclude that occurrence of GO alongside with LDH enhanced the removal efficiency of the tested anions naturally found in tap water. Moreover, it was observed that the modified materials NH1, NH2 and NH3 (same W/V =10 g/L) showed almost the same RE% for all anions studied. However, the nanohybrid NH1 with (W/V = 30 g/L) is highly recommended for the best anion removal from real water samples. The removal efficiency of two important heavy metals related to the water quality issue (Pb & Cd) was tested by applying all structures prepared as shown in The obtained results are in agreement with both Huang et al.  as well To sum up, the present effort would be recognized as a pioneer application for removal of both anions and heavy metals naturally found in a tap water sample by the prepared nanohybrids without experimental optimization. These results concluded that the prepared nanohybrids could work as dual function materials for elimination of different anions from the natural water as well as heavy metals at the same time.The current study applied the sheets of graphene oxide and the nanolayers of Zn-Al LDHs to produce well-designed nanohybrids to act as dual-effect adsorbents for removing different anions and two heavy metals from natural water. In this trend, these nanohybrids caused complete removal for sulfate and chloride anions. In addition, they removed the majority of fluoride, bromide and phosphate anions from the natural water. At the same time, these nanohybrids showed another positive effect for removal some heavy metals (cadmium and lead). It confirmed that the prepared nanohybrids can be used as dual-function nanohybrid materials for water purification. This dual-effect of the nanohybrids could be explained by creating new porous structures inside the materials prepared. In order to explain the behavior of the prepared nanohybrids toward removal of anions and heavy metals from natural water, the surface area and the porous structure of the nanohybrids NH1, NH2 and NH3 were studied and compared with the parent materials using Brunauer–Emmett–Teller (BET)  and Barr2/g as reported in 2/g. In the same trend, the surface area of both NH2 and NH3 became 61.50 m2/g and 60.3 m2/g, respectively. It means that the high efficiency of the nano hybrids can be due to the growth of the surface area. The porous structures of the nanohybrids were better than that of LDH because of new pores with a bigger size being created. The data in 3/g to the range of 0.08–0.290 cm3/g after combinating with graphene oxide. These pores were more suitable for trapping the different kinds of anions and heavy metals at the same time. These porous structures of the nanohybrids could be obtained by the nanolayers of LDH interacting with the nanosheets of graphene oxide, which act as a substrate for building the nanohybrids. According to our results, we conclude that the advantage of the dual-effect property of these nanohybrids enhanced the removal process of the different kinds of anions and the heavy metals from water in one stage only. It is likely the first time effective materials for eliminating of mono-valent, di-valent, and tri-valent anions were prepared alongside heavy metals in one step.The prepared nanohybrids represented high efficiency for removing five anions and two heavy metals even though the sizes of these species are different. This behavior was due to the sharp increasing of the surface area of the nanohybrids in comparison to pure LDH. The surface area of the pure LDH was 5.60 m


Search of new strategies for the inhibition of respiratory viruses is one of the urgent health challenges worldwide, as most of the current therapeutic agents and treatments are inefficient. Severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2) has caused a pandemic and has taken lives of approximately two million people to date. Even though various vaccines are currently under development, virus, and especially its spike glycoprotein can mutate, which highlights a need for a broad‐spectrum inhibitor. In this work, inhibition of SARS‐CoV‐2 by graphene platforms with precise dual sulfate/alkyl functionalities is investigated. A series of graphene derivatives with different lengths of aliphatic chains is synthesized and is investigated for their ability to inhibit SARS‐CoV‐2 and feline coronavirus. Graphene derivatives with long alkyl chains (>C9) inhibit coronavirus replication by virtue of disrupting viral envelope. The ability of these graphene platforms to rupture viruses is visualized by atomic force microscopy and cryogenic electron microscopy. A large concentration window (10 to 100‐fold) where graphene platforms display strongly antiviral activity against native SARS‐CoV‐2 without significant toxicity against human cells is found. In this concentration range, the synthesized graphene platforms inhibit the infection of enveloped viruses efficiently, opening new therapeutic and metaphylactic avenues against SARS‐CoV‐2. Present work shows that both electrostatic and hydrophobic interactions play a key role at the graphene/coronavirus interfaces and such materials can efficiently protect cells from coronavirus infections. While electrostatic interactions are responsible for the capturing of viruses, hydrophobic long alkyl chains can disrupt the envelop of the captured virions via hydrophobic interactions leading to a dual effect. SARS‐CoV‐2 belongs to the beta‐coronavirus genus. All coronaviruses have a lipid envelope with a capsid, which encapsulates the helical nucleocapsid with the RNA genome. The most prominent viral envelope component is the spike glycoprotein (S), which interacts with the angiotensin‐converting enzyme 2 (ACE2) on the surface of host cells and initiates virus entry, the first step of the SARS‐CoV‐2 infection cycle. Moreover, the polybasic cleavage site of S is found to play a crucial role in the binding between the virus and ACE2. Numerous efforts have been devoted to development of vaccines that generate neutralizing antibodies toward S to block viral interaction with ACE2. Similarly, the isolation and production of neutralizing antibodies targeting S promote the therapeutic treatment of SARS‐CoV‐2 infections, underscoring the importance of S as a target to block infection. However, it is also noticed that SARS‐CoV‐2 can mutate and it is conceivable that only small mutation of S by could render previously neutralizing antibodies ineffective. Therefore, it is essential to consider a new target instead of the S to develop materials for a broad‐spectrum inhibition of coronaviruses.SARS‐CoV‐2 poses a major threat to the public health worldwide, as it causes a respiratory disease named COVID‐19. Since the first case report in December 2019, a pandemic ensued with approximately one million deaths within the first nine months.1 SARS Hence, it is necessary to find a less toxic alternative for SARS‐CoV‐2 inhibition. Earlier reports have pointed out that negatively charged amphiphilic structures show broad‐spectrum inhibitory activity via the interaction with the viral envelope, including but not limited to herpes simplex virus (HSV), respiratory syncytial virus, human metapneumovirus, hepatitis C virus, ZIKA virus, etc. Surprisingly, in these studies with a fine tuning of charges and hydrophobicity, these compounds show low cytotoxicity but high virus inhibitory activity. The reason for such an observation could be due to the fast curing of membrane damages by self‐repairing mechanisms. Therefore, it is believed that the concept of envelope rupturing can be used to develop a robust SARS‐CoV‐2 inhibitor.Irreversible rupturing of the lipid viral envelope is a potential new approach for SARS‐CoV‐2 inhibition. Most of the surface‐active reagents, e.g., sodium dodecyl sulfonate, exhibit strong interactions with cellular membranes and can also rupture viral envelopes leading to inactivation of the virus, a so‐called virucidal compound. However, since they also act against the cellular membranes, they are highly toxic and can only be used for ex vivo disinfection of surfaces and hands.17 Hen Modified graphene nanoplatforms have shown significant inhibition of various pathogens due to their high binding affinity for bacteria and viruses. Even though the possible mechanisms of the interactions between graphene derivatives and pathogens are still a controversial topic, there are several suggested pathways for the antipathogenic action of these nanomaterials. Graphene materials are able to capture the pathogens by interactions with specific antibodies or ligands, electrostatic interactions, trapping or wrapping. Furthermore, graphene sheets can destroy the pathogens by hydrophobic or mechanical interactions. The versatility of nanoplatforms has been shown by their inhibition of various viruses, exemplified by designed inhibitors for HSV, African swine fever virus, alpha HSV, pseudorabies virus, and other viruses. In previous studies, graphene‐based compounds have been active against viruses mostly via a “binding and wrapping mechanism,” and have been virustatic inhibitors. Consequently, the virus is only temporarily inhibited from the interaction with host cells and the virus can escape from the inhibitor.Graphene, as a flexible 2D nanomaterial, is a promising candidate for the development of virus inhibitors due to the facilitated multivalent interactions at the functionalized interface.23 ModHerein, we report the development of graphene‐based virucidal compounds that rupture the envelopes of coronaviruses thus inhibiting viral infection irreversibly. The surface of graphene is functionalized with polyglycerol sulfate (PGS) and aliphatic chains of different length. In this study, we have investigated thoroughly how various sulfated graphene‐based materials interact with the virions of feline coronavirus (FCoV) and SARS‐CoV‐2 to explore the potential of designing virucidal graphene‐based inhibitors. A series of graphene platforms with PGS and alkyl amines of various chain lengths to surface of graphene is synthesized and compared for their inhibitory effect on coronaviruses. Functionalized graphene platforms that bear alkyl chains shorter than 10 carbon atoms show moderate infection inhibition without significant toxicity for cells. However, materials with longer aliphatic chains (>9 carbon atoms) indicate stronger inhibition and virion disruption of both coronaviruses, authentic SARS‐CoV‐2 and FCoV, but also exhibit higher toxicity for eukaryotic cells. Our results demonstrate a key role of electrostatics, i.e., polyglycerol sulfate coverage for virus capturing and a strong correlation between the length of alkyl chains and virucidal activity of such functionalized graphene‐based materials against coronaviruses.Figure x; x is the number of carbon atoms in aliphatic chains) were produced by our recently reported methods  . Each step of functionalization was proven using X‐ray photoelectron spectroscopy (XPS) due to the change in the elemental ratios both in survey and highly resolved C1s spectra . Afterward, alkyl amines with various length of chains were attached to the triazine functional groups of G‐PGS and graphene materials with dual alkyl amine/polyglycerol sulfate functionalities (G‐PGS‐Cx) were produced  proved successful attachment of polyglycerol and alkyl amines to graphene surface. To explore the impact of the length of aliphatic chains on the antiviral activity of graphene platforms, alkyl amines with a different number of carbon atoms  were conjugated to the surface of G‐PGS. The charge of the various graphene derivatives was not affected due to the attachment of alkyl chains  in comparison with G‐PGS (3.8 nm), according to the height and lateral size histograms of corresponding materials .In order to construct a platform for synergistic electrostatic and hydrophobic interactions with SARS‐CoV‐2 Figure 1a, graphs Figure .[23, ns Table –e, conju−1 considerably, the samples with shorter aliphatic chains (<10) did not show significant toxicity against the investigated cells lines , lung bronchial epithelial cells (HBE) and kidney Vero E6 cells was investigated by assessing the cells viability with the colorimetric assay Cell Counting Kit‐8 (CCK‐8). While samples with long aliphatic chains ≥10) reduced the cell viability at 50 µg mL0 reduceds  and G‐PGS‐C10 (9.8 ± 10.2 µg mL−1) . Therefore, material with the aliphatic chain length consisting of 11 carbon atoms showed the optimum values for the virus inhibition.Next, we studied inhibitory effects of the functionalized graphene platforms with FCoV, a coronavirus strain infecting cats. Though the S of FCoV and SARS‐CoV‐2 are slightly different, their envelope structures are similar, qualifying FCoV to be a surrogate to SARS‐CoV‐2 for inhibition studies. Plaque reduction assay showed dose‐dependent inhibition efficiency for the incubated compounds Figure 2a. In li1) Table . G‐PGS‐C−1) to quantitate virus replication  of 0.1, a procedure we refer to as pre‐infection treatment. After 24 h of infection, the cells were stained by anti‐FCoV antibodies to determine infection Figure –e. The nn Figure . Without−1, corresponding to an inhibitory effect higher than 99.9%. The cells also survived from the treatment, as the number of cells was not decreased, indicated by Hoechst 32 253 staining  were first incubated with the compounds a 1000 times higher concentration than their IC50 values for 1 h. After dilution to a concentration 10‐times lower than their IC50, the number of active virions was determined by plaque assay  were virustatic, the platforms with aliphatic chains ≥ 10  were virucidal. G‐PGS‐C11 was considered as the best material with two orders of magnitudes of virus titer reduction. The results of the plaque reduction assay and the virucidal assays showed that aliphatic chains more than 9 carbon atoms on the surface of graphene were necessary for virus membrane rupture  conditions, we used cryogenic transmission electron microscopy (cryo‐EM). Purified FCoV virions were incubated with G‐PGS‐C6 (virustatic) and G‐PGS‐C11  for 1 h and fixed by 2.5% formaldehyde. The samples were then cryofixated by plunge freezing and microscopically analyzed in a 200 kV TEM under low‐dose conditions Figure . Pristin and aliphatic chains interacted with the viral envelope  and FCoV IC50 for G‐PGS‐C11 were 42.6 ± 30.1 and 4.7 ± 0.7 µg mLmembrane.20 TheFigure −1, with a selectivity index (ratio of CC50 to IC50) of 86. Although G‐PGS‐C11 showed toxicity at high concentrations, the potent inhibition of SARS‐CoV‐2 at doses much lower than its CC50 value may allow safe antiviral treatment with this inhibitor. For example, G‐PGS‐C11 showed clear virus inhibition at 50 µg mL−1, a concentration where this compound did not show significant cellular toxicity. As shown in the image of the plaque reduction assays of Figure Finally, the inhibitory effect of the functionalized graphene platforms on authentic SARS‐CoV‐2 was studied using a plaque reduction assay Figure 4a,b. SimWe successfully synthesized graphene platforms with defined dual polyglycerol sulfate/aliphatic chains functionalities for SARS‐CoV‐2 binding and disintegration. In contrast with previously reported virustatic graphene‐based inhibitors, the synthesized inhibitors in this study were found to be virucidal. Virions bound to the functionalized graphene sheets by multivalent electrostatic interactions with the negatively charged PGS were disintegrated by the alkyl chains. Disruption of coronavirus envelopes occurred with elongation of aliphatic chains from G‐PGS‐C9 to G‐PGS‐C10 and showed the strongest inhibition and virucidality against feline coronavirus with G‐PGS‐C11. Therefore, alkyl chains should be long enough to exert efficient disintegration of the viral envelope. To rupture the envelop of the virus, the negatively charged PGS branches first interacted with the positively charged patches of the virion, then the aliphatic chains ruptured the membrane of the viral envelop. Graphene acted as a 2D platform to facilitate the interactions with virus particles. G‐PGS‐C11 displayed the most efficient antiviral properties against authentic SARS‐CoV‐2 without showing significant toxicity against eukaryotic host cells. The observed post‐treated effect and selectivity index of 86 opens the door for potential therapeutic applications.The compounds were 10‐fold diluted in Dulbecco's Modified Eagle's Medium (DMEM) and incubated with FCoV‐containing solutions with ≈100 PFU for 1 h at 37 °C. Afterward, the number of active virions was determined by plating the virus/compound mixture on a confluent monolayer of CRFK cells. Virus adsorption was allowed for 1 h before the supernatant was aspirated and replaced by a semi‐solid overlay of 1.3% methylcellulose (viscosity 400 cP). The overlay was removed after 48 h; cells were fixed with 4% formalin and stained with FCoV‐specific antibodies  to visualize plaques. The plaque reduction ratio was determined as following−1) were incubated with FCoV suspension containing ≈1 × 105 PFU for 1 h at 37 °C. Afterward, the mixture was diluted in DMEM medium 10‐foldly 5 times to an endpoint of no active virions. The number of active virions was determined by plaque assay and virus titers were calculated back by the respective dilutions.The functionalized graphene platforms  was propagated in Vero E6 cells and titrated via plaque assay.52 TheThe authors declare no conflict of interest.Supporting InformationClick here for additional data file.


To the best of the knowledge, for the first time, macroscale superlubricity on macroscale surfaces under ambient conditions is reported. The mechanism of macroscale superlubricity is due to the combination of exfoliated graphene flakes and the swinging and sliding of the GCS, which is demonstrated by the experimental measurements, ab initio, and molecular dynamics simulations. These findings help to bridge macroscale superlubricity to real world applications, potentially dramatically contributing to energy savings and reducing the emission of carbon dioxide to the environment.Friction and wear remain the primary modes for energy dissipation in moving mechanical components. Superlubricity is highly desirable for energy saving and environmental benefits. Macroscale superlubricity was previously performed under special environments or on curved nanoscale surfaces. Nevertheless, macroscale superlubricity has not yet been demonstrated under ambient conditions on macroscale surfaces, except in humid air produced by purging water vapor into a tribometer chamber. In this study, a tribological system is fabricated using a graphene‐coated plate (GCP), graphene‐coated microsphere (GCS), and graphene‐coated ball (GCB). The friction coefficient of 0.006 is achieved in air under 35 mN at a sliding speed of 0.2 mm s A tribological system is developed using a graphene‐coated ball, graphene‐coated microspheres, and a graphene‐coated plate. Macroscale superlubricity is realized using the developed system on macroscale surfaces under ambient conditions. The fundamental mechanisms of macroscale superlubricity are elucidated by ab initio and molecular dynamics simulations. This was originally proposed by Hirano and Shinjo in 1990.2), argon (Ar), reactive hydrogen (H2), and humid air.−1.2) environment between the diamond‐like carbon and graphene films, through the formation of nanoscrolls of graphene flakes wrapping the nanodiamond particles during the sliding.Mechanical friction dissipates about one third to one half of the energy in the world, and around 80% of machine component wear.Graphene was found in 2004 with an atomic layer of graphite.2) surfaces, absent from the catalysts and post‐transfer techniques. PECVD dissociates methane (CH4) at 900 °C by radiofrequency power, forming the carbon (C) source of graphene. This does not need the metallic catalysts or conductive substrates as those used in traditional CVD. The fundamental mechanisms of macroscale superlubricity were elucidated by ab initio and molecular dynamics (MD) simulations.In this study, macroscale superlubricity was performed under ambient conditions on macroscale surfaces, which was conducted on a newly developed tribological system coated by multilayer graphene (MLG). The MLG were deposited by plasma enhanced CVD (PECVD) powered by radiofrequency at 900 °C on quartz and silica  as the carrier and protective gas. MLG coated microspheres (GCSs) conducted by PECVD are dispersed between the graphene‐coated ball (GCB) and graphene‐coated plate (GCP)  Figure c,d. The ) Figure .Figure2. GCP, GCS, and GCB were coated with MLG by PECVD simultaneously in a tube furnace, without metal catalysts and post‐transfer treatment, reducing effectively the fabrication processes and contaminations induced by traditional CVD techniques.2 or dust particles induced during preparation processes by the vendor. Raman spectra of GCP, GCS and GCB are drawn in Figure −1 correspond to D, G, and 2D peaks, respectively.2g phonon at the Brillouin zone center. The 2D peak is the second order of the D peak, which stems from a process where momentum conservation is satisfied by two phonons with opposite wave vectors. It is always present without the requirement of defects for its activation.IG/I2D), indicates a MLG structure on the coated surfaces,2 substrates. Under the same growth processes, the gain size is less than 160 nm on curved and rough surfaces.After graphene deposition, all the surfaces turn dark Figure2d–f, cFigure−1. The resolution and accuracy of the developed tribometer was 0.01 mN, and the maximum load was 1 N. In Figure −1. The dynamic videos of macroscale superlubricity under 35 mN at 0.1 and 0.5 Hz are displayed in Movies S1 and S2 in the Supporting Information, respectively. In Figure −1 for 1200 s under ambient conditions on macroscale surfaces. To identify the function of the MS, the friction coefficient of GCP/MS/GCP is shown in Figure S1 in the Supporting Information. Under 30 mN at 0.1 Hz, the average friction coefficient of GCP/MS/GCP is 0.017, and the friction coefficient decreases first from 0.04 to 0.016 under 50 mN at 0.1 Hz, then increasing sharply to 0.7. The experiments demonstrate that the MLG on curved and flat surfaces plays the decisive role for the robust macroscale superlubricity under ambient conditions.FigureFigure3. Wear rate, Ws is calculatedV, N, and S are the wear volume, normal load and sliding distance, respectively. The wear rate calculated is 4.3 × 10−4 mm3 N−1 m−1. It is difficult to identify the wear area without the marking shown with a red dotted circle in Figure −1 in Figure alculatedWs=  VNSalculatedWs=  VNSFigureE0 per atom increases monotonically from 0 to 8°  and the plate (p). The elastic modulus and Poisson's ratio are 73.3 GPar calculated is 331, 351, 370, 387, 402, and 417 nm under normal loads of 25, 30, 35, 40, 45, and 50 mN, respectively. This confirms that the adding of MLGCMS could reduce the contact area. The maximum calculated aspect contact pressures are 1.32, 1.41, 1.48, 1.55, 1.61, and 1.66 GPa for a GCS under loads of 25, 30, 35, 40, 45, and 50 mN, respectively. These pressures are higher than 1 GPa calculated in microscale superlubricity.Lateral force, describedE∗=  1  −3−1 for 1200 s. After sliding, the defects on the wear areas of GCB and wear tracks of GCP are improved by adding GMS, as confirmed by Raman spectra. The wear on GCB and GCP in the macroscale superlubricity system is the lowest, which is difficult to discern compared with other systems under the same sliding conditions. Ab initio and MD simulations were employed to elucidate the mechanism of superlubricity, according to the experimental conditions observed for macroscale superlubricity. It was found that the swinging and sliding of GCS plays a crucial role for the realization of superlubricity. Our results pave a way for the design and fabrication of high‐performance devices with macroscale superlubricity, as well as for energy savings and reduction of emissions to the environment.In summary, the GCB/GCS/GCP tribological system was fabricated simultaneously in a tube furnace by PECVD, in which there are no metal catalysts and post‐transfer process. Macroscale superlubricity was realized on a flat quartz plate coated by MLG under ambient conditions, in which the normal load varies from 25 to 50 mN at a sliding speed of 0.2 mm s4Ra, root mean square (rms), and peak‐to‐valley (PV) values were 0.87 ± 0.03, 1.09 ± 0.04, and 9.13 ± 0.65 respectively on the polished surface, as illustrated in Figure S9a in the Supporting Information. After deposition with MLG, the surface roughness was improved for Ra, rms and PV to 0.76 ± 0.04, 0.96 ± 0.05, and 8.90 ± 0.59, correspondingly . The error bars for surface roughness were due to the five measurements on the polished surfaces prior to and after growth of graphene.Quartz plates had a length of 15 mm, a width of 15 mm, and a thickness of 2 mm. Prior to deposition, all the quartz plates were machined in a polisher  by lapping, mechanical polishing (MP), and chemical mechanical polishing (CMP) sequentially. During lapping and polishing, the polishing pressure and rotation speed were 40.6 kPa and 80 rpm, respectively. The machining time was 3, 10, and 25 min for lapping, MP and CMP, respectively. Abrasive papers with a mesh size of 3000, polyurethane, and nubuck were used as the lapping, MP and CMP pads, respectively. Deionized water was the lapping solution. MP slurry consisted of 2 wt% alumina, 0.1 wt% sorbitol, and deionized water. CMP slurry was made from the MP slurry through adding citric acid to a pH value of 5.4. The developed machining processes and slurries for the quartz plates were efficient and environment‐friendly, respectively. Surface roughness 2 powder or MS  were made of quartz, and the diameter of balls was 4 mm. Balls and polished plates were ultrasonically cleaned in alcohol for 10 min, and then dried by compressed air. Balls, plates and powder were put in a tube furnace of PECVD  simultaneously to deposit graphene films. Prior to deposition, the tube furnace was evacuated for 8 min to a vacuum of 5 Pa. Then, the tube furnace was heated, and the temperature was increased to 900 °C within 50 min with a flux of H2 at 20 standard cubic centimeter per minute (sccm). When the tube furnace was at 900 °C, the temperature was kept constant for 10 min with a flux of H2 at 20 sccm. During the deposition of graphene films, the power of the plasma was 250 W, and the flux of CH4 and H2 was 16 and 20 sccm, respectively. The deposition time was 30 min. To ensure the uniformity of graphene on the SiO2 powders, the temperature and pressure of CH4 and H2 were kept constant at 900 °C, 16 and 20 sccm during the deposition, which was significant for the uniformity of deposited graphene. In addition, prior to deposition, the SiO2 powders were ultrasonically dispersed in alcohol and sprayed on the quartz plate. The dispersed SiO2 powders were heated at 60 °C for 5 min, and then they were put in the tube furnace of PECVD for deposition. After deposition, the PECVD system was turned off, and the temperature was allowed to naturally reduce to room temperature. Prior to and after deposition, photographs of balls, plates and powder were taken by a camera . Wear tracks and coated MLG were characterized and measured by a field emission SEM , confocal Raman microscope , TEM  and laser scanning confocal microscope . TEM samples of the MLGCB were prepared by focused ion beam technique . MLGCMS were ultrasonically dispersed in alcohol for 1 min, and then picked up by a Cu grid used for preparation of TEM specimens. TEM samples of the GCP were prepared manually. First, two GCP specimens were glued face‐to‐face, cut by an ultrasonic cutter to a disc of 3 mm in diameter , lapped by a disc grinder system , polished by a waterproof abrasive paper with a mesh size of 2000, thinned at the central area by a dimple grinder to a thickness of ranging from 10 to 30 µm , and finally thinned by a precision ion polishing system . Surface roughness was measured by a non‐contact surface profilometer .The balls  and SiOTribological tests were performed on a developed homemade tribometer.−5 eV, and a k‐point grid of 21 × 21 × 1 was employed to calculate the electronic structure. The cutoff energy of a plane wave was 500 eV. During the calculation of energy, the top layer of graphene was rotated for 40° from the initial equilibrium position, and the atoms were migrated stepwise for 40 steps until reaching the final positions.Ab initio calculations were carried out in the Vienna ab initio simulation package (VASP) using the projector augmented wave (PAW) method.r is the distance between pairs atoms.C‐Si, σC‐Si, and rC‐Si were 0.0096 eV, 3.0 Å, and 10 Å, respectively.−1. When touching the GNC, the downward movement of GCP was stopped. During sliding, the normal load was applied and consistently kept at 500 nN on the top GCP, NC and bottom GCP. Sliding was performed on the length direction of the GCP, and the speed and distance were 5 m s−1 and 5 nm, respectively.The GCP/GNC/GCP tribological performance was conducted by MD simulations. Both plate and NC were set as rigid bodies composed of a silicon single crystal. The two plates and NC were wrapped with four‐layer graphene to perform the superlubricity analysis, which was consistent with the macroscale superlubricity from the experiments. One‐layer graphene was fixed on the plate to simulate the coated MLG on the quartz plate during the experiments. Two‐layer atoms were fixed on two edges of the four‐layer graphene wrapped on two plates. For the four‐layer graphene wrapped on the NC, two‐layer atoms were fixed along the horizontal diameter. Each plate had a length of 44 nm, a width of 6.4 nm, and a thickness of 2 nm. The diameter of the NC was 6 nm. The four‐layer graphene on the plate had a length of 40 nm and a width of 6.4 nm. As the length of graphene was over six times that of the diameter of the NC, the boundary effect was effectively suppressed. The four‐layer graphene had a thickness of 1.035 nm, and the interlayer distance was 0.3445 nm. The interactions of C—C, Si—Si, and C—Si covalent bonds were simulated by the adaptive intermolecular reactive empirical bond order (AIREBO), Tersoff and 6–12 Lennard‐Jones (LJ) potentials, respectively.. The Ball, NS and plate were made of amorphous SiO2,2 were calculated by AIREBO and Tersoff potentials, respectively.2 interaction, and ε = 0.0024 eV, σ = 0.34 nm for graphene layers. The scratching simulations of GCB/GCP and GCB/GNS/GCP systems were performed with LAMMPS code, and visualized by AtomEye.To investigate the tribological properties with and without GNS, MD models were constructed on GCB/GCP and GCB/GNS/GCPThe authors declare no conflict of interest.Z.Y.Z. and Y.F.D. contributed equally to this work. Z.Y.Z. and D.M.G. conceived the projects. Z.Y.Z. wrote the paper. All authors commented on the manuscript prior to submission. Y.F.D. designed and performed the experiments of macroscale superlubricity. S.L.H. and S.Z.L. conducted the molecular dynamics simulations. L.L.C. and K.K.C. carried out the ab initio simulations. W.X.X. carried out the chemical mechanical polishing experiments. Z.Y.Z., Y.F.D., F.N.M., C.C.Z., Y.L., C.‐T.L., and I.P.P. analyzed the mechanisms of macroscale superlubricity. All authors discussed the results and commented on the manuscript.Supporting InformationClick here for additional data file.Supplemental Movie 1Click here for additional data file.Supplemental Movie 2Click here for additional data file.Supplemental Movie 3Click here for additional data file.Supplemental Movie 4Click here for additional data file.Supplemental Movie 5Click here for additional data file.Supplemental Movie 6Click here for additional data file.Supplemental Movie 7Click here for additional data file.


During nuclear maturation of most eukaryotic pre-messenger RNAs and long non-coding RNAs, introns are removed through the process of RNA splicing. Different classes of introns are excised by the U2-type or the U12-type spliceosomes, large complexes of small nuclear ribonucleoprotein particles and associated proteins. We created intronIC, a program for assigning intron class to all introns in a given genome, and used it on 24 eukaryotic genomes to create the Intron Annotation and Orthology Database (IAOD). We then used the data in the IAOD to revisit several hypotheses concerning the evolution of the two classes of spliceosomal introns, finding support for the class conversion model explaining the low abundance of U12-type introns in modern genomes. The process of RNA splicing is a necessary step in the maturation of nearly all eukaryotic pre-messenger RNAs and many long non-coding RNAs. During this process, introns are excised from primary RNA transcripts, and the flanking exonic sequences are joined together to form functional, mature messenger RNAs ,2. In moThe large-scale and well-organized online databases of genomic data, like Ensembl , UCSC 99 and RefMany features of eukaryotic introns have been examined for clues about their evolutionary history. Introns can be assigned to one of three phases based on their position relative to the codons of the flanking exonic sequence: phase 0 introns fall directly between two codons, phase 1 introns fall between the first and second nucleotides of a single codon, and phase 2 introns fall between the second and third nucleotides of a single codon. It has long been noted that introns are not evenly distributed between the three phases ,28. In cIn an effort to address some of the many open questions about intron evolution, we created the Intron Annotation and Orthology Database (IAOD), a database of intron information for all annotated introns in 24 genomes, including plant, fungal, mammalian, and insect genomes. It also uniquely annotates orthologous introns, and assigns intron class using the intronIC algorithm described herein . The website is publicly accessible at introndb.lerner.ccf.org.To begin, intronIC identifies all intron sequences in an annotation file by interpolating between coding features (CDS or exon) within the longest isoform of each annotated gene. For each intron, sequences corresponding to the 5′ splice site  and branch point sequence (BPS) region (from −55 to −5 relative to the last base of the intron) are scored using a set of position weight matrices (PWMs) representing canonical sequence motifs for both U2-type and U12-type human introns. A small ‘pseudo-count’ frequency value of 0.001 is added to all matrix positions to avoid zero division errors while still providing a significant penalty for low-frequency bases. For all scored motifs, the binary logarithm of the U12/U2 score ratio (the log ratio) is calculated, resulting in negative scores for introns with U2-like motifs, and positive scores for introns with U12-like motifs. Because U2 introns are not known to contain an extended BPS motif, the PWM for the U2-type BPS is derived empirically using the best-scoring U12 BPS motifs from all introns in the final dataset whose 5′SS U12 scores are below the 95th percentile. To identify the most likely BPS for each intron, all 12-mer sequences within the BPS region are scored and the one with the highest U12 log ratio score is chosen. This initial scoring procedure follows the same general approach used by a variety of different groups for bioinformatic identification of U12-type introns ,33–36.et al., the 5′SS and BPS scores together are sufficient to produce good binary clustering of introns into putative types, due to strong correspondence between the 5′SS and BPS scores in U12-type introns  and negative (U2-type) training sequences for the SVM  and U12-type (GT-AG/AT-AC) introns, and sets of high-confidence U2- and U12-type intron sequences with which to train the SVM classifier Figure . Due to ata from  to incluM Figure . In ordeM Figure ).C, which is (roughly) the degree to which misclassification of data in the training set is penalized during the creation of an optimized (i.e. wide) margin separating the positive and negative classes. To our knowledge there is no single, standard approach for establishing the best value of C; we chose to optimize C using an iterative cross-validation method which starts with a wide range of logarithmically-distributed values and narrows that range based upon the best-performing  value of C in each validation round. After several such iterations, the mean of the resulting range is taken as the final value of C to be used to train the classifier. Balanced accuracy is used as a performance metric due to the highly imbalanced nature of the training data, where the negative class (U2-type) greatly outnumbers the positive class (U12-type). Because the human training data is very well-separated, when applied to intron sequences in the human genome values of C ≥10 perform equally well during cross-validation  than taking the default ‘best’ parameter value via the scikit-learn API, which simply returns the first rank-1 parameter value found. For the human genome, this approach results in a classifier which performs perfectly on the training sets, with both F1 and precision-recall AUC scores of 1.0 on held-out training data  and the modified version used for this application is available at (https://github.com/Devlin-Moyer/IAOD).For the purpose of populating the IAOD, intronIC was slightly modified to produce a single output file containing all of the annotation information recorded in the IAOD for each intron—the default version is available for download from , release 39 of Ensembl Metazoa, or release 40 of Ensembl Plants , and al.1; ref. ). LastlyA custom Python script created a PostgreSQL database using the output of intronIC, the lists of gene symbols from BioMart, and the list of orthologous groups of introns. All of the orthologous groups were inserted in a table with two columns: a unique numeric ID for each group and a list of all intron labels belonging to that group. One table for each genome contains, for each intron: the abbreviated sequence (see above), taxonomic and common names of the organism, name of the genome assembly, intronIC score, intron class (determined from the intronIC score), intronIC label, chromosome, start coordinate, stop coordinate, length, strand, rank in transcript, phase, terminal dinucleotides, upstream exonic sequence (50 nt), 3′ terminus with the branch point region enclosed with brackets (40 nt), downstream exonic sequence (50 nt), full intron sequence, Ensembl gene ID, Ensembl transcript ID, and gene symbol. Another table with identical fields contains all U12-type introns from all genomes., an open-source Python web development framework, and Bootstrap 4.0.0, an open-source framework for front-end web development. The search engines use the Django ORM to interact with the PostgreSQL database.The website was constructed using Django 2.0There are four search engines on the website: the main, advanced, U12, and orthologous searches. The main and advanced search interfaces have input fields corresponding to individual columns in the database, so the text input in each field can easily be matched with the appropriate column using the Django ORM. The U12 search engine uses PostgreSQL search vectors to allow users to make full text queries against the database. I.e. users can input a string containing one term corresponding to as many fields as they like and get a result. However, if the search query contains, e.g., the names of two different species or genes, no results will be returned, since no single record (intron) in the database corresponds to multiple species or genes. This limits the number of possible queries, but allows for a simple user interface for simple queries concerning U12-type introns. Since the main and advanced search engines require users to specify which field of the database each term of their query corresponds to, it does not need to use full text search vectors, and can consequently accept multiple search terms for each field. The homolog search engine also makes use of PostgreSQL search vectors to find the row of the homolog table containing the intron ID input by the user.p = 1 − (1 − x)m−1, where x is the proportion of U12-type introns in the genome and m is the average number of introns in the genome. Data from the IAOD was used to obtain n, x, and m for each genome in the database that contained at least one U12-type intron. The dbinom function in R was used to compute the probability of observing the observed number of genes with multiple U12-type introns in each genome. If U12-type introns were randomly inserted a genome, we would expect the distribution of U12-type introns per gene to be binomial with parameters n = number of genes with at least one U12-type intron and To ensure that the observed clustering of U12-type introns in the same genes was not an artefact of U12-type introns with alternative splice sites being recorded as distinct U12-type introns, all intron coordinates listed by intronIC were used to create a graph where each node corresponded to a position within each genome (e.g. GRCh38 + chr1 + 492045 corresponds to base pair 492045 on chromosome 1 in assembly GRCh38 of the human genome) and two nodes are joined with an edge if they appear in the same row of the list of intron coordinates. In this graph, alternatively spliced introns are evident as clusters of >2 nodes, so each cluster represents a single intron, regardless of how many alternative splice sites it possesses. A single edge from each cluster was selected and the corresponding coordinates were matched to the original intronIC output to get accurate counts of the total number of unique introns in each class in all genomes annotated in the IAOD.Homo sapiens using a machine-learning (SVM) classifier to assign each intron a probability of being U12-type  in human. In Arabidopsis thaliana, our method matches the calls in the U12DB 94% of the time (223/238), with similar results  for U12-type introns from the plant-specific database ERISdb  our method categorized only 1/116241 introns as U12-type, suggesting a false-positive rate of less than 0.001%. A total of 8967 U12-type introns were identified using this technique. Groups of analyzed introns in conserved regions of homologous genes were also annotated; collectively, these data constitute the Intron Annotation and Orthology Database (IAOD).We developed the method intronIC , implemented in Python, and used it to perform genome-wide identification of U2- and U12-type spliceosomal introns in 24 eukaryotic species including 14 vertebrate animals, 5 invertebrate animals, 4 plants and two yeasts. For each species, type-specific position-weight matrices (PWMs) for the 5′ splice site and branch point sequences were used to create score vectors for every intron in each genome. These score vectors were then compared against corresponding vectors in high-confidence training sets from Homo sapiens, D. melanogaster, A. thaliana and Ciona intestinalis to the whole genomes of every other organism in the database  replicated their findings in all 21 genomes  are in conserved positions, while out of the 9527 U2-type introns in such regions of the human genome, 2098 (22%) are in conserved positions in A. thaliana. Thus, our comparative analysis is consistent with U12-type intron enrichment in the ancestral eukaryotic genome relative to the most U12-intron-rich extant lineages.Basu et al.  argued tGallus gallus and Tetraodon nigroviridis (Table The majority of introns annotated in the IAOD in both classes begin with GT and end with AG Table , in agreis Table . Inspectis Table  largely is Table ,36,63.Interestingly, We have created a database of intron annotation and homology information and used it to investigate several evolutionary hypotheses regarding the two classes of spliceosomal introns in eukaryotes. We have also created a web-based interface for querying this database to facilitate further investigations. The relationships between intron class, phase, terminal dinucleotides and -1 nucleotides at the 5′ splice site and the nonrandom distribution of U12-type introns annotated in the IAOD do not support many previous models that explain these patterns ,30,50,51introndb.lerner.ccf.org and all code used to create the database and run the website is available at the following GitHub repository https://github.com/Devlin-Moyer/IAOD. The standalone intronIC algorithm is available at https://github.com/glarue/intronIC.The IAOD is publically accessible at gkaa464_Supplemental_FileClick here for additional data file.


These CISe NHJs exhibit surprising non-linear emissions, quantized transitions, large carrier mobility, low trap-state-density, long carrier lifetime and possible up-conversion. They facilitate efficient separation of minority carriers, reduce recombination and essentially function like quantum materials. This approach mitigates the material issues and complex fabrication of incumbent nanoscale heterojunctions; it also overcomes the flexibility and scale-up challenges of conventional planar pn junctions. The self-stabilized CISe NHJ film can be roll-to-roll processed in ambient atmosphere, thus providing a promising platform for a range of optoelectronic technologies. This concept exemplified by CISe compounds can be adapted to create nano-scale pn junctions with other inorganic semiconductors.Pairing semiconductors with electrochemical processing offers an untapped opportunity to create novel nanostructures for practical devices. Here we report the results of one such pairing: the in-situ formation of highly-doped, interface-matched, sharp nanocrystalline homojunctions (NHJs) with single step electrodeposition of two copper-indium-selenide (CISe) compounds on flexible foil. It produces a homogenous film, comprising inherently ordered, 3-dimensional interconnected network of  High performance planar pn junctions often require complex, expensive processing techniques with limited scalability. Fabricating materials systems with low-cost processes that intrinsically host nano-scale pn junctions, such as bulk heterojunctions (BHJs) offers an attractive alternative platform for optoelectronic technologies. Solar cell efficiencies for perovskite quantum dot, organic BHJ and polycrystalline perovskite devices have reached 18–25% range1. But significant challenges remain to improve their stability, toxicity, upscaling and reproducibility6. Here we show how pairing certain inorganic semiconductors, such as copper indium selenide (CISe) compounds with electrochemical processing produces high quality nanostructures that could potentially overcome such issues to enable realistic electro-optic device applications.Semiconductor 2-alloys for over 20% efficiency. The CISe ODCs offer further choice of direct bandgaps (Eg) in the 1.04–1.34 eV range and intrinsic doping with shallow donor and acceptor defects that imparts n- or p-type conductivity9. The intrinsic doping of CISe ODCs with shallow donor  and acceptor (VCu) defects has been theoretically established8. The defects impart n-type or p-type conductivity to the CISe nano grains. These attributes remain largely unexploited for device fabrication. For instance, the dual-type conductivity of CISe-ODCs could realize distinct nano-scale pn junctions10. Additionally, the CISe-ODC compositions are self-stabilized and thus allow single step electrodeposition (SSE) of stoichiometric compounds from a single aqueous electrolyte, which greatly simplifies upscaling to roll-to-roll manufacturing in ambient atmosphere12. This work exploits both ODC attributes to form nanocrystalline homojunction (NHJ) films that could overcome the above issues of the state-of-the-art BHJs and similar nanostructure.The CISe family of ordered defect chalcopyrites (ODC) compounds features a unique combination of desirable functional properties, including: high optical-absorption, high defect tolerance, low toxicity, exceptional longterm stability and established performance of CuInSe2, CuIn3Se5, or mixed CuInSe2-CuIn3Se5 compositions on stainless steel (SS) foil13. A brief low temperature air anneal stabilizes the intrinsic defect distribution and crystallizes the CISe into 4–35 nm grains. The nanocrystalline CISe films comprise strongly bound, spatially resolved, interlinked, space-filling grains, with excellent adhesion10. Initial electro-optical studies indicated that the SSE-made CuInSe2-CuIn3Se5 mixture offered surprising potential for efficient and stable NHJ devices. It revealed unexpected optoelectronic attributes related to the morphology, conductivity and composition of SSE-made CISe films. For instance, electrochemical electroreflectance (EER) spectra for the CISe film indicated high structural order and well crystallized chalcopyrite structured grains of CuInSe2 and CuIn3Se5; and CuInSe2-CuIn3Se5 (≡ CuIn2Se3.5) complexes10. An unexpected trend was discerned, showing lower photocurrent transients for films with CuIn2Se3.5 composition than for the films with excess non-complexed CuInSe2 or CuIn3Se513. These first results highlight the unique and intriguing aspects of specific CISe compositions. They warrant in-depth probing into their electro-optical properties and their relationship to film composition and morphology to fill in the knowledge gaps. A profound understanding will enable exploiting the attributes of the SSE-made CISe films for efficient and easily manufactured pn NHJ devices. Here we combine photoluminescence (PL), time-resolved microwave conductivity (TRMC), capacitance/impedance (C/I) and atomic force microscopy (AFM) methods to uncover more remarkable aspects, concerning the local morphology and carrier dynamics for the CISe NHJ films.Unravelling the reaction mechanism for CISe formation enabled the SSE of stoichiometric CuInSe2+/In3+/Se4+ solution at a fixed potential, Fig. 2 strips with graded composition for the (T) top, (M) middle and (B) bottom sections along the strip length, Fig. 2.SSE produces CISe ODC films from a CuT, M and B sections, CISe films S1 and S2, Table 3Se5 at 4.8°K (inset), which includes emissions from both CuInSe2 and CuIn3Se514, but without the superimposed fine structure that is evident for the new sets of spectra. The 830 nm filter blocks emissions from energies > 1.4 eV and selectively transmits the PL from the shallow states near the edge of Eg for CuIn3Se5, Fig. 2 (0.95 eV), large peak (1.3 eV) for higher order ODCs and a smaller peak (1.73 eV). The 3 sections of film S1 essentially show the same PL intensity and spectral features in both sets of spectra, which likely reflects the nonexistence of significant composition gradient for film S1.PL was measured with a 532 nm laser for the T, M, B sections but with varying compositions for film S2, Table T), S2(M), S2(B), sections while the spectral features remain the same. With the 830 nm filter, S2(T) and S2(M), having Cu:In:Se ratio closer to CuInSe2 show similar PL intensity, while the In-rich S2(B) with composition closer to CuIn2Se3.5 exhibits lower PL response. With the 540 nm filter, S2(T) still shows higher intensity but the peak PL intensity of the S2(M) slightly lower than for S2(B). The presence of varied bulk content of these different stoichiometric ratios is consistent with a respectively weighted intensity of those two regions of PL. The trend for reversal of PL peak intensity could have resulted from local inhomogeneity wherein the complexed and non-complexed [CuIn3Se5] or [CuInSe2] grains respond somewhat differently to the light transmitted by 540 and 830 filters. The intensity variation trend for S2(B) or S2(M) with different filters may not be significant, the overall PL emission intensity could be associated with the extent of the [CuInSe2–CuIn3Se5] complexation in the film as previously observed with other techniques13. The previously trend of lower photocurrent transients was seen for CISe films comprising CuInSe2-CuIn3Se5 complex (≡ CuIn2Se3.5). Conversely, films comprising excess [CuIn3Se5] or [CuInSe2] show higher PL intensity (and faster charge transport) than the films comprising [CuIn3Se5] ≈ [CuInSe2].Figure g fine structure for the 3 regions of film S2 appear identical despite significant composition variation that merely reduces the PL emission intensity from S2(T) to S2(B), Fig. 2 PL peak; enhanced PL for CuIn3Se5; similar PL feature at 1.4 eV; much larger PL at 1.73 eV; 3.5 times higher PL intensity; and more intricate fine structure. The fine structure likely arises from specific sub-Eg emissions, originating from shallow native defect states near the conduction band (CB) or valence band (VB) edge of the nanostructured S1 and S2 films. They are located near the Egs of CuInSe2, CuIn3Se5 and CuIn5Se8 and an unidentified feature at 1.73 eV. The predominantly near-Eg emissions correspond to free-carrier-to-shallow defect transitions and band-to-band transitions from specific states. For example, the transition peaks at: 1.20 eV ≡ shallow donor state in CuIn3Se5; 1.26 eV ≡ CB; 1.31 eV and 1.37 eV ≡ energy levels inside CB or ≡ shallow donor states from CuIn5Se8. Such shallow defect transitions enable efficient charge separation within the p-CuInSe2/n-CuIn3Se5 complex, as evidenced by the EER data10.Surprisingly, the overall PL spectral features and the superimposed sub-E2 Eg, such as: 1.00 eV ≡ (CB → VCu) or ≡ (InCu → VB); 0.93 eV ≡ (InCu → VCu); 0.88 eV ≡ (VSe → VCu) or (InCu → VB). The PL emissions from 1.2 − 1.5 eV occur near the Egs  of CuIn3Se5 and CuIn5Se8. Interestingly, the CLS fitting shows that the superimposed fine structure is typically spaced at 30 mV. It is intriguing that the composition variation does not change the fine structure.The PL spectrum in Fig. g emission peak, centered around 1.73 eV is seen for both samples S1 and S2, but is more pronounced for film S2. It appears to encompass the Egs of In2Se3 (1.8 eV) and Se (1.7 eV). The CISe NHJ band structure could contain defect states associated with these compounds, which were incidentally not discerned by other methods13. Alternatively, the blue shift may ensue from grain size effects. Intra-grain and band-to-band transitions were detected by EER for the p-CuInSe2/n-CuIn3Se5 complex10. The peak also shows ~ 30 mV spaced fine structure, e.g. 1.69, 1.73, 1.76, 1.79 eV. The apparent quantization of states likely results in quantum confined nano-regions in the CISe film that possibly contribute to this large PL emission. The emission of multiple and narrow emission lines is a hallmark of photon upconversion in nanoparticles. It entails stepwise low energy photon absorption, energy transfer and the emission of high energy photons, i.e., quantized electronic transistions can transmute sub-Eg photons into higher energy (above-Eg) photons. Such upconversion phenomena are often observed in core–shell nanoparticles and transition metals18. In the present scenario, it apparently results from the near quantum dot sized CISe nanocrystals that fortuitously lead to the above-Eg quantized states. Significantly this approach allows quantum confinement without introducing external rare earth dopants into the host material as in state-of-the-art upconversion18. Linking this self induced nonlinear optics phenomenon to the CISe NHJ electronic structure could reveal a new avenue for electro-optical applications.The PL data implies that the optical and electronic properties of the CISe film are intimately related via a quantum system, comprising quantized energy levels. The unexpected broadening in PL spectral range resulting from the above-E2 film, S3. The In-rich sections, S1(B) and S2(B) were chosen for these measurements, Table 20. The CISe films: S1(B), S2(B), and S3, were delaminated from the SS foils and transfered to a low-dielectric loss quartz substrate using a double-sided tape transfer method. The samples were excited by 10 Hz 500 nm laser pulses during continuous dry N2 purge.Transient photoconductivity analysis was carried out using TRMC for same films as PL, S1 and S2 along with a third stoichiometric CuInSeB), S2(B), and S3. The TRMC figure of merit is given by φΣμ, corresponding to the peak product of free-carrier generation yield (φ) and sum of free electron and hole mobilities (Σμ). The φΣμ was quite low at (3.9 ± 0.5) × 10–3 cm2/Vs for sample S3, with CuInSe2 composition. Bi-exponential fits of the 500 ns photoconductivity transient decays gave an average lifetime approaching the instrument response of the microwave cavity of less than 30 ns. Sample S1(B) with ~ CuIn2Se3.5 composition showed dramatically improved φΣμ of 1.9 ± 0.4 cm2/Vs, nearly 1000 × larger than S3, yet the average weighted lifetime extracted from the fitted photoconductivity transient was still as short as S3 and nearly instrument response limited; TRMC free carrier lifetimes this short are not promising for useful device applications that rely on bulk charge transport. In contrast, sample S2 (B) with ~ CuIn3Se5 stoichiometry exhibited a φΣμ of ca. 3 cm2/Vs with a remarkable average weighted photoconductivity lifetime of 740 ns (fitted from 500 ns of data). To verify the long lifetime in this sample, the signal collection window was expanded to 2 µs and confirmed the lifetime at 727 ns. Also in contrast to S3 and S1(B) samples, the S2(B) exhibited a strong dependence of photoconductivity lifetime on excitation intensity; above an absorbed photon flux of 1 × 1010 cm−2 the lifetime decreased, but below this absorbed flux there was no intensity dependence. One explanation may be that the sharp pn NHJs in this composition serve as charge recombination centers at higher carrier densities, especially given that for nanocrystals of this size, the microwave photoconductivity signal is dominated by inter-grain carrier dynamics. Even so, the TRMC data confers with the PL data for S1 and S2. It implies that the observed shallow defect transitions may  be responsible for the extraordinary attributes of film S2, and likely contribute to its long carrier lifetime.Figure The following electrical characterization provides further insights into the electronic properties and structure of SSE-made CISe films. AFM topography in Fig. pn junction generates electron–hole pairs that can significantly affect the minority carrier concentration, hence the Fermi energy level and the width of the depletion region. This enables the TUNA photocurrent to distinguish the predominant conductivity type. Figure T) and S4(B) areas, Table 1. The images show that the p-CISe grains (4d) generate higher photocurrent under positive bias, whereas the n-CISe grains (4e) generate more photocurrent under negative bias. The switching of photocurrent polarity with applied bias provides visual evidence that the currents originate from individual p-CISe and n-CISe domains, coexisting within the same film. Both types of grains were present in the entire film, although the S4(T) and S4(B) areas exhibited stronger p-type and n-type response, respectively. Note that the different photocurrent scale bars in Fig. D) ranges in p- and n-grains. These observations are consistent with the Cu-rich and In-rich compositions for the S4(T) and S4(B) sections in Table Shining a laser on a D value was outside the sensitivity range, i.e. < 1014 or > 1021. Electrolyte impedance spectroscopy was performed in the frequency range of 100 kHz to 1 Hz for analogous CISe film S5. Figure V) versus capacitance (C) and 1/C2 for film S5. It shows high capacitance (tens of microns), ND > 1021 cm−3, and flat band potential of − 0.2 V vs. Ag/AgCl. The high values for ND are consistent with the VCu and InCu defect-doped, In-rich n-CISe ODC such as CuIn3Se5. The p-CISe was close to CuInSe2 stoichiometry10. The widely different NDs, outside the SCM range for the two conductivity types is probably the reason for lack of SCM contrast. Based on this rationale and the respective defect structure, we tentatively assign the very high doping ND (> 1021 cm−3) for the n-CISe grains and the very low doping ND (< 1014 cm−3) for the p-CISe grains. Admittance spectroscopy results indicate minimal frequency dependence of defects even at 300°K, Fig. 21. The Mott–Schottky and impedance data, stating the ND and the absence of deep defects corroborates with theoretical treatments that the intrinsic defects in n-CISe are shallow11. The shallow intrinsic defects are uniformly distributed within the nano grains and most of these grains are uniformly and intrinsically doped (1021/cm−3 ≡ one doping site per nm3). The shallow defects allow free carrier flow without trapping, avoid degeneracy and enhance grain-to-grain current flow.Despite the strong photocurrent response, scanning capacitance microscopy (SCM) contrast was not detected for film S4, possibly because its Npn junctions with neutralized electrical charges. Figure pn junctions, Fig. p-grain and n-grain, forming high quality pn NHJ. The sharp pn interface acts as a barrier to recombination of minority carriers; it could enhance current flow through devices, such as solar cells. Besides illustrating the different conductivities and pn junction formation, the combined AFM and EBIC results map out the conductive nature of the distributed grains in addition to the physical distribution of grains.Comparing the topography and AFM micrographs for film S4 on the same 1 µm wide area indicates that the very prominent, bright nanograin agglomerates in Fig. p-CISe and n-CISe nanocrystals that interconnect in a 3-dimensional (3D) network. The electrical potential gradient, ∇U at the pn NHJ interface separates the electron–hole pairs that are generated in each nanograin, Fig. pn junctions enables fast separation of electron and hole carriers. Electrons move through the n-CISe and holes through the p-CISe. The continuous generation of separated electrons and holes contributes to the high carrier density. This creates and maintains a chemical potential gradient, ∇μ to drive the transport of electrons and holes separately along the p-CISe and n-CISe grains, Fig. pn junctions primarily utilize the ∇U while exitonic devices utilize the ∇μ22. Unlike either of such device configurations, the CISe NHJ has the potential to effectively utilize both of the fundamental driving forces, i.e. ∇U  ≈ ∇μ, as shown in Fig. p and n electrodes the CISe NHJ layer forms a device with the configuration of: foil/n-cathode/n-CISe/p-CISe/p-anode, Fig. nF, EpF the valence band (VB) and conduction band (CB) edges for the n-CISe and p-CISe, respectively. The band-to-band transitions in (i) p-CISe and (ii) n-CISe nanograins as well as the intra-grain (i + iii), (ii + iv) transitions nanograins were previously derived from EER spectra10. This combination of intra-grain and band-to-band transitions within the CuInSe2-CuIn3Se5 complex could efficiently separate minority carriers, moving the holes to anode and the electrons to cathode. Suitable carrier selective contacts electrodes are needed to produce highly efficient p-CISe/n-CISe NHJ devices.These results indicate that under specific conditions, SSE spontaneously creates highly-ordered OC of 0.6 V and photocurrent of up to 23 mA/cm2 under 33 mW/cm2 illumination. But the efficiency obtained was ~ 5%, mainly due to the low fill factor that is expected for devices without carrier selective interlayers. Yet, based on the premise of low recombination in CISe NHJ space charge region, the low fill factor likely arises from recombination at the CISe/back contact or the series resistance of the device due to poor CISe/front contact interfaces. Thus, carrier selective electrodes could essentially prevent such interface leakages to maximize device efficiency. These preliminary photovoltaic metrics are especially promising given the completely unoptimized nature of the proof-of-concept devices and the low Eg of the CISe absorber. Thus, if optimized CISe NHJ device can be achieved with fill factor in the range of current peroskite devices of ~ 80%1 the efficiency could reasonably approach the 20% efficiency benchmark.Although solar cell efficiency is not the primary focus of this paper, we have tested several preliminary devices with the architecture of SS/CISe/TCO without appropriate carrier-selective electrodes; they exhibit VD and sharp pn junctions that indicate efficient charge carrier dynamics suggest that the CISe nanocrystals may work as quantum particles. Quantum confinement within CISe nanocrystals evidently generates the unusual opto-electronic properties. Such confinement could produce discrete spaced transitions within quantized states and contribute to the unexpected above-Eg PL emission. The fact that PL spectra are well-resolved even at 300°K attests to the unique quality of SSE-created CISe films. Only very pure and high quality crystals or artificially created quantum dot structures have shown similar transitions and non-linear absorption, and in those cases only under cryogenic conditions unlike here, where it is observed at room temperature. Moreover, the electronic nanostructure of CISe NHJ can tolerate wide composition variation, i.e. CISe films with In/Cu ratios from 1.3 to 2.5 give essentially the same PL spectra. This is in stark contrast to the precise composition and electronic configuration required for standard devices and the associated high fabrication costs. The direct deposition of CISe pn NHJ resolves many issues with the existing approaches, used to fabricate conventional planar pn junctions, perovskite/organic/inorganic bulk heterojunctions or inorganic ordered heterojunctions. Significantly, the CISe grains have highly desirable matching interfaces since they grow into each other as pn junctions. This finding solves a major hurdle for creating inorganic pn junctions. The exceptionally stable, non-toxic CISe NHJ avoids other issues of the nano pn junction devices, in particular the doping difficulties, separate synthesis and physical mixing of two material types. However, many of the carrier selective electrodes deployed in such devices can be utilized to produce the CISe NHJ device of Fig. The electronic properties concur and strongly support the PL and TRMC data. The shallow defects, high Npn NHJ. Its unexpected properties, including PL spectral range broadening, quantized emissions and the long lifetime, imply non-linear behavior similar to that seen in artificially designed quantum dot structures. Quantum confinement within CISe nanocrystals evidently generate discretely spaced quantized states. Specific charge carrier transitions within these states may be responsible for their unusual opto-electronic properties. Notably, the quantum confinement is enabled without external rare earth dopants into the host material. The extraordinary attributes of specific CISe films may be linked to the reaction kinetics during SSE that create special CISe morphologies with CuInSe2-CuIn3Se5 complexes.Coupling electrodeposition with CISe semiconductors creates scalable thin-film of nano n-CISe and p-CISe grains co-existing in same film. The cell geometry during SSE determines the predominance of Cu-rich p-CISe or In-rich n-CISe grains in the film. The n-CISe exhibits much higher ND and photocurrent than p-CISe. Shallow defects that intrinsically dope the CISe films appear to be uniformly distributed within the nano grains at the rate of one doping site per nm3. SSE naturally creates 3D network of highly-doped, interface-matched, sharp, abrupt p-CISe/n-CISe NHJs in-situ. These CISe pn NHJ potentially utilize both of the fundamental driving forces, i.e. ∇U  ≈ ∇μ, to reduce recombination, enhance carrier separation and transport, and thus boost future device performance. Band-aligned, carrier selective electrodes are sought to transition the CISe NHJ into high performance devices.The SSE-made films comprise pn NHJs that could essentially perform like crystalline 2D planar pn junctions or artificially ordered 3D nanostructures1 without their fabrication complexities. The results also call attention to the rarely explored ODC semiconductors that offer a plethora of relevant properties to produce nanostructures of technological interest. The resulting absorbers/emitters can be directly used in electro-optic devices with minimum manipulation. They offer new perspectives for processing devices with atmospheric roll-to-roll SSE. Such fabrication can impact a variety of the flexible electronics for next-generation optical communications, sensing, and imaging applications27. The resulting device roll can be fashioned into inexpensive flexible solar panels, or directly incorporated in solid-state lighting devices, photoelectrodes and other energy conversion. Overall, the SSE method efficiently balances the critical parameters for inorganic electro-optic devices: performance, stability, cost and scalability, for a variety of flexible devices in simple thin-film form factor.SSE presents a generic, very low-cost processing platform to create high quality 2 SS foil using Technic’s high speed flow cell or on a 3 cm2 SS foil in a beaker. Experimental conditions were varied to obtain samples with different CISe composition, including external dopants. The electrolyte pH was adjusted to ~ 2 during the deposition, with NaOH or HCl solution. Sufficient CuCl solution was added to the electrolyte to deposit roughly CuIn2Se3.5 compositions. Se was added to maintain a [Se2]/[Cu+] ratio between 3 and 6. The formation of In-rich CISe-ODC compounds requires excess of In3+ concentration and slightly higher pH. The films were annealed using an IR lamp (650 W) at 90% power with 2–3 s pulses, repeated 10–15 times in ambient atmosphere. Film composition and thickness were analyzed at multiple spots across the sample area with Spectro Midex XRF spectrometer.The SSE of CISe films was performed in 0.15 M NaCl aqueous electrolyte containing specific Cu:In:Se concentration ratio at 60 °C. The films were deposited on 117 cm2 to the Na2SO3 (pH 3) electrolyte held in a 3-electrode cell. Lock-in ampliflier was used in a frequency range of 100 kHz to 1 Hz to obtain capacitance values and Electrolyte Impedance Spectroscopy.Electrochemical characterization was performed on masked CISe samples, exposing an area of 0.25 cm34. Since the CISe films were deposited onto SS foil, which would short the microwave cavity, the films were transferred to low-dielectric loss quartz substrates (25 × 11 × 1  mm3) using a delamination-and-tape-transfer process. Single wavelength excitation pulses at 10 Hz (ca. 5 ns pulse width) and 500 nm were generated by a 355 nm pumped optical parametric oscillator (Continuum) on the signal arm of the output. A series of absorptive neutral density filters were used to attenuate the excitation power over 3 orders of magnitude, and the beam area was diffused to uniformly illuminate the entire cross-section of the q-band waveguide, providing uniform optical pumping over the entire area of the sample (~ 2.5 cm2). The microwave cavity was purged continuously with dry nitrogen during all measurements.PL emission spectra were obtained at 300°K (room temperature), using Horiba’s Micros setup with a 532 nm laser excitation. Long pass filters were used to block the short wave light below 540 nm or 830 nm; the data were not corrected for the grating spectra. Contactless probing with TRMC provided relevant photoelectric response of CISe films. The technique and its application to photoresponsive materials has been described in explicit detailp-type and n-type grains in the film. CISe sample S1 was cut and mounted on a metal disk with Ag-paste. Topological and nano-electrical AFM-TUNA micrographs were obtained on 1 µm area, using Bruker Dimensional Icon and SCM-PIT or SCM-PTSI probes, under AC bias of 5 V, lift height of 100 nm and scan rate of 0.5 Hz. This system included Kelvin probe force microscopy (KPFM) and scanning capacitance microscopy (SCM). The dark lift mode was used to eliminate the laser effects on the minority carrier concentration, hence the Fermi energy level and the width of the depletion region. The adjunct SCM, KPFM techniques were used to discern surface variations in carrier concentration and work function between the tip/CISe sample.AFM-TUNA measurements used bias polarity effects to distinguish between EBIC micrographs were obtained by Ephemeron, Inc using Mighty EBIC 2.0 on ITO/CISe/SS device at 10 V made from film S6.


Sarcoidosis is a multisystem inflammatory disorder and can affect any organ; however, ureteric involvement is extremely rare with only four cases reported in the literature to date, all of which were diagnosed with surgical ureteral resection including a nephroureterectomy. This study reports the first case of ureteric sarcoidosis controlled with medical therapy where a differential diagnosis was performed based on the diagnostic clue of hypercalcemia. A definitive diagnosis was established without surgical resection of the ureter.A 60-year-old man presented with anorexia and weight loss. Blood tests showed renal dysfunction and hypercalcemia. Computed tomography revealed left hydronephrosis associated with left lower ureteral wall thickening, which showed high signal intensity on diffusion-weighted magnetic resonance imaging. Similarly, we detected a bladder tumor on cystoscopy, and a 2-cm-long stenosis was revealed by retrograde ureterography; therefore, ureteral cancer was suspected. Meanwhile, considering the clinical implication of hypercalcemia, a differential diagnosis of sarcoidosis was established based on elevated levels of sarcoidosis markers. Fluorodeoxyglucose positron emission tomography showed fluorodeoxyglucose accumulation in the left lower ureter, skin, and muscles, suggestive of ureteric sarcoidosis with systemic sarcoid nodules. For a definitive diagnosis, transurethral resection of the bladder tumor and ureteroscopic biopsy were performed. Histopathological examination revealed ureteric sarcoidosis with bladder urothelial carcinoma. Following an oral administration of prednisolone, hypercalcemia instantly resolved, the renal function immediately improved, and the left ureteral lesion showed complete resolution with no recurrence.In this case, the co-occurrence of ureteral lesion with bladder tumor evoked a diagnosis of ureteral cancer. However, considering a case of ureteral lesion complicated with hypercalcemia, assessment for differential diagnosis was performed based on the calcium metabolism and sarcoidosis markers. In cases of suspected ureteric sarcoidosis from the assessment, pathological evaluation with ureteroscopic biopsy should be performed to avoid nephroureterectomy. Sarcoidosis is a multisystem inflammatory disorder characterized by the formation of non-caseating granulomas and can affect any organ . HoweverA 60-year-old man with no medical history or comorbidities presented with anorexia and weight loss (from 59.4 kg before admission to 55.9 kg on admission). No findings were observed on physical examination. Blood tests showed renal dysfunction  and hypercalcemia . A urine test revealed hypercalciuria without proteinuria  revealed left hydronephrosis associated with left lower ureteral wall thickening, which showed high signal intensity on diffusion-weighted magnetic resonance imaging Figs. a, b, 4a.3 2D3, 151.0 ng/L, normal range: 20.0–60.0 ng/L) and sarcoidosis markers: angiotensin-converting enzyme , lysozyme , and soluble interleukin-2 receptor . Neither 25-hydroxyvitamin D (25(OH)D), parathyroid hormone (PTH), nor parathyroid hormone-related peptide (PTHrP) was elevated: levels of 25(OH)D, PTH and PTHrP were 23.3  ng/mL, 15.0  pg/mL and <  1.1  pmol/L, respectively  has been implicated as a potential cause of sarcoidosis . Sarcoid2D3 by non-caseating granulomas has been implicated in calcium metabolism disorder. An elevated level of 1,25-(OH)2D3 enhances intestinal calcium absorption and promotes osteoclastic activity and bone resorption, resulting in hypercalcemia and hypercalciuria [Calcium metabolism disorder, characterized by hypercalcemia and hypercalciuria, which were recognized in this case, is a clinical feature in sarcoidosis. Hypercalcemia and hypercalciuria occur in approximately 5% and 40–62% of sarcoidosis patients, respectively . An incralciuria –10.Calcium metabolism disorder is the most important cause of renal dysfunction. Several different mechanisms, including vasoconstriction of arterioles, acute tubular necrosis, impairment of urinary concentrating ability caused by decreased sensitivity to antidiuretic hormone, and nephrocalcinosis, have been implicated in renal dysfunction . In the The present case met the diagnostic criteria of sarcoidosis: a compatible clinical and/or radiological image, histopathologic evidence of non-caseating granulomas, and exclusion of other diseases with similar findings, such as infections or malignancy . The ind2D3 and sarcoidosis markers . However, it should be noted that urothelial carcinoma is rarely complicated by hypercalcemia as paraneoplastic syndrome [2D3 is similarly reported to be one of the inducers of paraneoplastic hypercalcemia [2D3, would be needed to clarify the cause of hypercalcemia. Finally, ureteroscopy is a useful tool, which can facilitate more precise pathological diagnosis [In the present case, the co-occurrence of ureteral lesion with bladder tumor evoked a diagnosis of ureteral cancer. Meanwhile, the clinical manifestation of hypercalcemia served as a clue to the differential diagnosis of ureteric sarcoidosis through the elevated levels of 1,25-(OH)syndrome –16. In tsyndrome . In uretiagnosis . In the In conclusion, in the cases of ureteral lesions complicated with hypercalcemia, assessments for differential diagnosis based not only on calcium metabolism markers but also on sarcoidosis markers should be performed as a first step. This can help decide whether subsequent examinations for ureteric sarcoidosis are necessary. In the event ureteric sarcoidosis is suspected after the initial assessments, pathological evaluation with ureteroscopic biopsy should be performed, as ureteric sarcoidosis with hypercalcemia can be controlled with medical therapy, thus avoiding nephroureterectomy.