In situ synthesis of NiMn-LDH-decorated CuCo2O4 core–shell nanoflowers on copper foam for high-performance supercapacitor

Abstract

The development of supercapacitors with high energy density and excellent multiplicity faces a key technological hurdle: optimizing energy storage and charge transfer efficiency in electrode materials. To address this, this research successfully synthesized ultrathin core–shell nickel–manganese layered double hydroxide (NiMn-LDH) materials by employing an interface modulation technique aimed at the precise design of electrode configurations. This material was synthesized through hydrothermal in situ growth on CuCo₂O₄ (CCO) using copper foam (CF) as both the substrate and copper source, creating a distinctive three-dimensional hierarchical structure. The experimental findings indicated that the resulting CCO@NiMn-LDH/CF electrode demonstrated outstanding electrochemical characteristics: it achieved an ultra-high specific capacity of 3040.67 F g⁻¹ at a current density of 1.0 A g⁻¹ and maintained a capacity retention of 80% at 5.0 A g⁻¹, all while exhibiting remarkable cycling performance at elevated current densities. To further validate its practical applications, a hybrid supercapacitor featuring CCO@NiMn-LDH/CF as the positive electrode and activated carbon (AC) as the negative electrode was developed in this study, and it achieved an energy density of 71.5 Wh kg⁻¹ at 800 W kg⁻¹. This fully substantiates the extensive application potential of this core–shell structured electrode in electrochemical energy storage systems.