CuCo2S4@MnO2 hollow porous heterostructure for high-performance supercapacitors

Abstract

The design and synthesis of hollow porous heterostructures from multiple components is expected to impart excellent properties to the electrochemically active materials owing to their high internal voids, high surface area, and high pore volume, which are beneficial for electrolyte infiltration. However, the development of optimized electrode materials for hollow porous heterostructure storage fell behind expectations. To address these challenges, we prepared a CuCo2S4@MnO2 composite on a foam nickel substrate to create a hollow porous heterostructure. The optimized composite possesses high areal capacitance of 14.9 F cm−2 (or a specific capacitance of 1643 F g−1) at 3 mA cm−2, and 83.4% capacitance retention after 30,000 cycles in a three-electrode configuration. The NF@CuCo2S4@MnO2//AC asymmetric supercapacitor can achieve high energy density (1.2 mWh cm−2) and power density (2.4 mW cm−2) due to the wide cell voltage in aqueous electrolyte and high particular capacitances from both CuCo2S4 and MnO2 improved by the hollow porous heterostructure. Furthermore, the NF@CuCo2S4@MnO2//AC ASC can light up an LED display screen. Overall, this work demonstrates the great potential and broad prospects for application in energy storage of hollow porous heterostructures.