Algorithm-Driven Optimization of ZnCo₂O₄@CuO Core-Shell Architectures for High-Performance Supercapacitors

Muhammad Shahzad; Syed Usman Tanveer

Authors

Muhammad Shahzad Department of Physics Government College University Lahore
Syed Usman Tanveer Department of Space Science, Punjab University

Keywords:

Electrochemical Performance, Spinel Metal Oxide, Capacitance, Electrical Conductivity

Abstract

This study investigates the electrochemical performance of ZnCo₂O₄@CuO core–shell nanostructures as advanced electrode materials for supercapacitors. ZnCo₂O₄, a spinel metal oxide, offers high theoretical capacitance and environmental compatibility but suffers from low electrical conductivity and structural instability. To address these limitations, we synthesized ZnCo₂O₄@CuO composites using a hydrothermal method, leveraging CuO's excellent electrical conductivity and chemical stability to enhance the core material's properties. Comprehensive characterization confirmed the formation of a hierarchical core–shell structure with improved surface area and uniform elemental distribution. Electrochemical testing revealed that ZnCo₂O₄@CuO electrodes exhibited significantly enhanced specific capacitance (882 F g⁻¹ at 4 mA cm⁻²), superior rate capability, and excellent cycling stability, retaining ~90.2% of their initial capacitance after 4000 cycles. An asymmetric supercapacitor device assembled with these electrodes delivered a maximum energy density of 46.66 Wh kg⁻¹ and power density of 800 W kg⁻¹. These findings demonstrate the potential of ZnCo₂O₄@CuO core–shell nanostructures as high-performance, durable, and cost-effective materials for next-generation energy storage applications.

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