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Thermoelectrics are critical for sustainable energy development because they allow for the direct conversion of waste heat into electricity, improve energy efficiency in a variety of applications, and provide a clean, dependable, and maintenance- free alternative for power generation. In recent days, metal chalcogenides have gained more attention in the field of thermoelectrics. Among the chalcogenide materials, Tin Selenide is a promising material for mid-temperature thermoelectric applications, whereas Bismuth Telluride is mainly known for its room-temperature thermoelectric applications. The combination of these two materials would probably enhance the performance of the thermoelectric generator. The present work deals with bilayer and multilayer thin film deposition of Tin Selenide and Bismuth Telluride on the glass substrates by physical vapor deposition. Then the deposited thin films were given a post-annealing treatment for 30 minutes at 323 K, 423 K, and 523 K. The structure and morphology of the thin films have been studied using X-Ray Diffraction (XRD), Scanning Electron Microscopy(SEM), Field Emission Scanning Electron Microscopy(FESEM) and Atomic Force Microscopy (AFM). The Seebeck Coefficient and Electrical conductivity of the bilayer and multilayer thin films were studied using the Seebeck Coefficient measurement system as temperature as function in a range of 300K to 573 K. The maximum Seebeck Coefficent of -350μV/K was obtained for both bilayer and multilayer thin film at 573 K. The highest electrical conductivity of 220S/m and 170S/m were obtained for bilayer and multilayer thin film respectively. The power factor that gives the thermoelectric generator's performance was calculated from the Seebeck Coefficient and Electrical conductivity. The overall power factor for 573 K annealed films of bilayer and multilayer thin films increases with rise in temperature. The maximum obtained power factor for bilayer and multilayer thin films were 25W/K2m and 18 W/K2m respectively. An increase in the annealing temperature leads to improved thermoelectric performance for both bilayer and multilayer thin films. [ABSTRACT FROM AUTHOR]

Nanocrystalline phase pure Tin Oxide (SnO2) materials were prepared by chemical co-precipitation method. The materials were prepared using water and 2-propanol as the co-solvents taken in 1:1 ratio. The role of varying the molar concentrations of the raw material and the effect of calcination temperature on the structural, optical, and the electrochemical properties of the SnO2 were explored. The stoichiometric ratio of Tin: Oxygen was found to be 1:2 in all the cases as observed from the EDAX studies. Irrespective of the calcination temperature, the SnO2 made using the 0.4 M of Tin source outperformed other materials in terms of electrochemical performance owing to the good synergy between structural and optical properties. The above material calcinated at 800 °C exhibited an outstanding specific capacitance of 580 F/g at a current density of 1 A/g. Electrochemical impedance spectroscopy indicates the capacitive behavior of the material. [ABSTRACT FROM AUTHOR]

Because of their enormous potential for use in current electronic systems, polymer-based dielectric materials have garnered considerable attention. The spatial distribution of fillers has a significant impact on the dielectric behavior of polymer composites, so a better understanding of the relationship between the dielectric properties of composites and the spatial distribution of filler would be extremely helpful in developing new high-performance dielectrics. In this study, anatase TiO2 and hexagonal boron nitride (h-BN) nanocomposites were prepared by ball-milling. This was followed by the preparation of poly(vinylidene fluoride)–co-hexafluoropropylene (PVDF-HFP)-based polymer nanocomposites. TiO2/h-BN material was confirmed by x-ray diffraction (XRD) analysis. The TiO2/h-BN nanoparticles were well distributed in scanning electron microscopy (SEM) images, with very little particle aggregation. The Fourier transform infrared (FTIR) spectroscopy data indicate that the nanocomposite components interact well. AC impedance spectroscopy was used to investigate the variations in electrical characteristics including dielectric constant, dielectric loss and electrical resistivity (Nyquist plot) of the prepared composite film. These films were applied to enhance load-bearing capacity during electrostatic force state, making use of flexible fabric-based metal electrodes. The load-bearing capacity of the film was determined by measuring the tensile strength. The PVDF-HFP/TiO2/h-BN nanocomposite showed flexibility in addition to dependable dielectric capabilities, making it potentially suitable for a variety of flexible electronic devices such as electroadhesion and electrostatic storage devices. [ABSTRACT FROM AUTHOR]

Pure nanocrystalline SnO2 powders calcined at three different temperatures of 400, 600 and 800°C have been successfully synthesized by chemical co-precipitation method with the starting material SnCl2·2H2O and 2-propanol as a precursor. The crystallite sizes of 10, 12 and 15 nm were obtained for three different temperatures, respectively, and the rutile tetragonal structure was confirmed by XRD pattern. SEM micrographs of all the samples were found to be particulate agglomerated and further crystallite size increases as the temperature increases. The peaks of EDAX reveal that the prepared sample constitutes purely tin and oxide atoms. UV–visible spectra show that the bandgap energy values were 3.05, 3.36 and 3.20 eV. Photoluminescence studies exhibit relative intensity of 422 nm, a small broad peak and somewhat intense peak at 440 nm for the samples annealed at 400, 600 and 800°C. The specific capacitance values of the prepared samples were found to be 380, 335, 548 F g–1 for the samples annealed at 400, 600 and 800°C from cyclic voltammetric studies. Galvanostatic charge–discharge analysis predicts the faradic redox reaction from its symmetric curves. [ABSTRACT FROM AUTHOR]

In this study, a semi-organic crystal of L-tryptophan hydrochloride (LTHC) has been synthesized and quality crystals has been grown using a slow evaporation technique. Singe crystal XRD confirms the monoclinic system with space group P21. UV optical studies displays the transmittance in the entire visible region. The Mulliken charge distribution and MEP mapping show significant charge transfer due to nucleophilic and electrophilic moieties. The molecule's chemical reactivity was examined using HOMO-LUMO and MESP investigations. The crystal's nonlinear properties were studied using the Kurtz-Perry method. These findings suggest that LTHC crystals may have potential applications in the field of nonlinear optics. [ABSTRACT FROM AUTHOR]

In this study, Nanocrystalline Indium and Vanadium doped SnO2 multiwalled Carbon nanotube composite is prepared by simple sol-gel process. The Nanocomposite produced was Ultrasonicated for five minutes. The impact of Ultrasonication on the surface modification of MWCNT, structural and optical properties was analysed. The sample was characterized by X-ray diffraction, scanning electron microscopy, UV-visible absorption and Laser Raman Spectroscopy studies. A comparative study was done between the as-prepared and Ultrasonicated sample. The X-ray diffraction revealed the improved crystallinity of the Ultrasonicated sample. The UV-Visible spectrum gave the size dependent absorption and transmittance in the visible region. The SEM images show that ultrasonication enhances the full coverage of the MWCNT and very less agglomeration on the surface. The percolation was not much pronounced on the samples sonicated after five minutes. [ABSTRACT FROM AUTHOR]