Electrosynthesis of Y2O3 nanoparticles and its nanocomposite with POAP as high efficient electrode materials in energy storage device: Surface, density of state and electrochemical investigation

Herein, high-purity Y2O3 nanopowder has been synthesized by the electrochemical method. The crystal structure of the compound has been investigated by means of X-ray diffraction (XRD). In order to evaluate the bonding characteristics of the obtained compound, Fourier transform infrared spectroscopy (FTIR) was carried out. Morphological properties of the nanopowders were examined through field emission scanning electron microscopy (FE-SEM). Furthermore, thermal studies were investigated through the thermogravimetric analysis (TGA). Not only from the XRD spectrum but also using the Nelson-Riley functions, various surface parameters referring to Y2O3 nanoparticles, e.g. particle size, texture coefficient and lattice constant, were determined. Additionally, Modified Scherer's Scherrer's formula (Williamson-Hall-isotropic strain model) was utilized to predict micro strain introduced into electrosynthesized Y2O3 nanoparticles. Full potential periodic density functional theory was used to derive detailed structural and electronic information of Y2O3 crystal. Revised Perdew-Burke-Ernzerhof (PBE) exchange-correlation functional was used for bulk structure relaxation and all post-processing calculations such as band structure and density of state (DOS) calculations were done with Heyd-ScuseriaErnzerhof (HSE) method. Then, hybrid POAP/Y2O3 films, acting as active electrodes in electrochemical super capacitor applications, were prepared through poly orthoaminophenol (POAP) electropolymerization in the presence of Y2O3 nanoparticles in order to enhance the electrochemical performance of the conductive polymer. The energy storage behavior observed for the prepared composite film can be attributed to synergistic effect existing between Y2O3 nanoparticles and the conductive polymer.