Indian Institute of Technology Kharagpur

About: Indian Institute of Technology Kharagpur is a education organization based out in Kharagpur, India. It is known for research contribution in the topics: Computer science & Dielectric. The organization has 16887 authors who have published 38658 publications receiving 714526 citations.

Self-powered flexible Fe-doped RGO/PVDF nanocomposite: an excellent material for a piezoelectric energy harvester

Abstract: In this work, we report the superior piezoelectric energy harvester ability of a non-electrically poled Fe-doped reduced graphene oxide (Fe-RGO)/poly(vinylidene fluoride) (PVDF) nanocomposite film prepared through a simple solution casting technique that favors the nucleation and stabilization of ≈99% relative proportion of polar γ-phase. The piezoelectric energy harvester was made with non-electrically poled Fe-RGO/PVDF nanocomposite film that gives an open circuit output voltage and short circuit current up to 5.1 V and 0.254 μA by repetitive human finger imparting. The improvement of the output performance is influenced by the generation of the electroactive polar γ-phase in the PVDF, due to the electrostatic interactions among the –CH2–/–CF2– dipoles of PVDF and the delocalized π-electrons and remaining oxygen functionalities of Fe-doped RGO via ion-dipole and/or hydrogen bonding interactions. Fourier transform infrared spectroscopy (FT-IR) confirmed the nucleation of the polar γ-phase of PVDF by electrostatic interactions and Raman spectroscopy also supported the molecular interactions between the dipoles of PVDF and the Fe-doped RGO nanosheets. In addition, the nanocomposite shows a higher electrical energy density of ≈0.84 J cm−3 at an electric field of 537 kV cm−1, which indicates that it is appropriate for energy storage capabilities. Moreover, the surface of the prepared nanocomposite film is electrically conducting and shows an electrical conductivity of ≈3.30 × 10−3 S cm−1 at 2 wt% loading of Fe-RGO.

Recent advances of metal–metal oxide nanocomposites and their tailored nanostructures in numerous catalytic applications

Abstract: The skilful synthesis of nanohybrids composed of noble metals (Au, Ag, Pt and Pd, as well as AuAg alloy) and metal oxides (ZnO, TiO2, Cu2O, MnO2, Fe2O3, WO3 and CeO2) has received considerable attention for applications in photocatalysis, solar cells, drug delivery, surface enhanced Raman spectroscopy and many other important areas. The overall architecture of nanocomposites is one of the most important factors dictating the physical properties of nanohybrids. Noble metals can be coupled to metal oxides and metal chalcogenides to yield diverse nanostructures, including noble metal decorated-metal oxide nanoparticles (NPs), nanoarrays, noble metal/metal oxide core/shell, noble metal/metal oxide yolk/shell and Janus noble metal–metal oxide nanostructures. In this review, we focus on the significant application based advances in neat and tailored nanostructures of noble metal–metal oxide nanohybrids and touched upon chalcogenides also. The improvement in performance in representative energy conversion, electrochemical water splitting, photocatalytic hydrogen generation, photocatalytic CO2 reduction, photocatalytic degradation of organic pollutants and dye-sensitized solar cell (DSSCs) applications is discussed. Finally, we conclude with a perspective on the future direction and prospects of these controllable nanohybrid materials.