Control of crystalline structure and ferroelectric properties of Pb(ZrxTi/sub 1-X/)O3 films by pulsed laser deposition
We have investigated Pb(Zr/sub X/Ti/sub 1-X/)O/sub 3/ (PZT) films on Pt/SiO/sub 2//Si substrates formed by pulsed laser deposition (PLD) and subsequent rapid thermal annealing (RTA) under various growth conditions. X-ray diffraction analysis revealed that preferentially [100]-oriented perovskite PZT films with trigonal structure were formed after RTA from as-deposited films which had consisted of small grains with pyroclore structure. The degree of [100]-orientation of the PZT film increased with the oxygen partial pressure during PLD. The capacitors made from these films showed higher remnant polarization than those from randomly oriented films.
Ferroelectricity versus Antiferroelectricity in the Solid Solutions of PbZrO3 and PbTiO3
The phase diagram of the solid solutions of PbZrO 3 –PbTiO 3 system has been established by investigating dielectric, dilatometric, calorimetric and structural properties. In Pb(Zr97–Ti 3 )O 3 four...
Single step formation of biocompatible bimetallic alloy nanoparticles of gold and silver using isonicotinylhydrazide.
Manufacturing nanoparticles with controlled physicochemical properties using environment-friendly routes have potential to open new prospects for a variety of applications. Accordingly, several approaches have been established for manufacturing metal nanoparticles. Many of these approaches entail the use of hazardous chemicals and could be toxic to the environment, and cannot be used readily for biomedical applications. In the present work, we report a single step bio-friendly approach to formulate gold (Au), silver (Ag), and Au-Ag alloy nanoparticles with desired surface corona and composition using isonicotinylhydrazide (INH) as a reducing agent. INH also functioned as a stabilizing agent by enabling a surface corona around the nanoparticles. Remarkably, within a single step INH could also provide a handle in regulating the composition of Au and Ag in bimetallic systems without any additional chemical modification. The physicochemical and surface properties of the different nanoparticles thus obtained have been examined by analytical, spectroscopic and microscopic techniques. Cell cytotoxicity (release of lactate dehydrogenase), cell viability and intracellular reactive oxygen species (ROS) assays confirmed that the Au, Ag, and Au-Ag bimetallic nanoparticles prepared with INH are biocompatible. Finally, the presence of organic surface corona of INH on the nanoparticles was found to impart nanozyme activity and antimycobacterial sensitivity to the nanoparticles.