Improved ZnWO4@NiCo2O4 core–shell nanosheet arrays with regulatory interfaces and electronic redistribution

Abstract

ZnWO₄@NiCo₂O₄ core–shell nanosheet array composites are synthesized on nickel foam via a two-step hydrothermal method. The optimal conditions, including a Ni(NO₃)₂·6H₂O to Co(NO₃)₂·6H₂O molar ratio of 2 : 1, 12 hours reaction time, and 120 °C temperature, yield a specific capacitance of 875 C g⁻¹ at 1 A g⁻¹. The electrode also maintains 81.1% capacitance after 10 000 cycles. The material's performance is attributed to its core–shell structure, which enhances ion diffusion and electron transport. This study presents a viable approach for high-performance supercapacitor electrodes.