Engineering NiO/ZnO/Co3O4/MXene nanocomposites via hydrothermal route for next generation supercapacitor

Abstract

In this study, a mixed metal oxide nanocomposite of NiO/ZnO/Co₃O₄ and its MXene based hybrid composite were synthesized via a hydrothermal reaction for electrochemical energy storage applications. X-ray diffraction (XRD) confirmed the formation of crystalline multiphase oxide structure, while Scanning Electron Microscopy (SEM) revealed irregular and non-uniform nanoparticle. Energy-dispersive X-ray spectroscopy (EDS) mapping confirm uniform and homogenous distribution of Ni, Zn, Co and other constitute in nanocomposite. Electrochemical performance was evaluated using galvanostatic charge-discharge (GCD), Electrochemical Impedance Spectroscopy (EIS), and Cyclic Voltammetry (CV). From CV analysis, NiO/ZnO/Co₃O₄ exhibits specific capacitance of 988 Fg⁻¹ within potential window of 0–0.6 V, which further enhance to 1402 F g⁻¹ (0–0.6 V) when hybridized with MXene, proving beneficial impact of MXene in enhancing capacitive behavior. Based on GCD analysis, NiO/ZnO/Co₃O₄/MXene composite yields excellent specific capacitance of 1128.34 Fg^− 1 at 1 Ag^− 1 (0–0.6 V) with maximum cycling stability of 86.57% at 7,000 cycles, thus providing remarkable rate capabilities. EIS findings reveals, decrease in charge-transfer resistance, indicating improves charge-transfer efficiency due to higher electrical conductivity. MXene incorporation, suggests improved electrical conductivity and faster charge-transfer kinetics. These results indicate that the NiO/ZnO/Co₃O₄/MXene hybrid is a promising electrode material for high-performance electrochemical energy storage applications.