Nickel oxyhydroxide/zinc hydroxide/rGO as a promising candidate for hybrid energy storage and clean energy generation

Abstract

AbstractMetal hydroxides are the upcoming materials in the field of energy storage applications. In this work, a mixed metal hydroxide‐based carbon composite, that is, nickel oxyhydroxide/zinc hydroxide/rGO, was successfully synthesized through single step hydrothermal process. The synthesized material was thoroughly characterized using x‐ray diffraction, Fourier transform infrared spectroscopy, Raman spectroscopy and field emission scanning electron microscopy. Detailed electrochemical analysis was performed through cyclic voltammetry, constant current charge‐discharge analysis and electrochemical impedance spectroscopy. The material exhibited impressive values of specific capacitance (541 F/g), energy density (75 Wh/kg) and power density (2592 W/kg). The electrodes were found to be sufficiently robust and reliable. A symmetric storage device was also fabricated using the synthesized composite followed by thorough electrochemical analyses of the same. A flexible piezoelectric nanogenerator was fabricated by impregnating the polymer PVDF with the synthesized composite that yielded an open circuit voltage of ~50 V and power density of 3117 W/m3. This opens up the possibilities of using the developed material in real life applications.