Effect of Nickel doping on Cobalt Oxide Nanoparticles for energy storage applications

Abstract

Abstract We present a comprehensive study on the utilization of Ni-doped Co3O4 nanoparticles for energy storage applications, particularly in supercapacitors. X-ray diffraction analysis confirms the structural integrity and phase purity of the samples, exhibiting the characteristic peaks of the cubic spinel structure X-ray photoelectron spectroscopy confirms the presence of Co, Ni, and O elements, with different valence states observed. Scanning electron microscope images reveal irregular nano-flakes with increased particle size and reduced porosity as Ni doping concentration rises. Electrochemical analysis, including cyclic voltammetry and galvanostatic charge-discharge tests, demonstrates promising performance. Specifically, the 3 wt% Ni-doped Co3O4 sample exhibits a maximum specific capacitance of 299 F/g at a scan rate of 5 mV/s. The GCD profile of all the three Ni doped Co3O4 Nps were carried out. All of them revealed quasi triangular charge-discharge curve that are due to both pseudo capacitive and electric double layer process. Moreover, the 3% Ni-doped Co3O4 nanoparticles demonstrate a maximum specific capacitance of 347 F/g at a scan rate of 1.5 A/g. Additionally, the 5% Ni-doped Co3O4 nanoparticles exhibit an impressive capacity retention of 92.87% even after 1500 cycles. Our findings indicate that appropriate Ni doping on Co3O4 nanoparticles enhances their electrochemical performance, great potential for supercapacitor applications.