Hydrothermal synthesis of mesoporous MnCo2O4/CoCo2O4 ellipsoid-like microstructures for high-performance electrochemical supercapacitors

Abstract Design and fabrication of unique micro/nanostructural MnCo2O4-based electrode material for applications in supercapacitors with excellently electrochemical performance is still of great challenge. In this work, novel MnCo2O4/CoCo2O4 ellipsoid-like (MCE) microstructures were synthesized through a facile hydrothermal route with a post annealing treatment in air. Such MnCo2O4/CoCo2O4 composite possessed a specific surface area of 42.2 m2 g−1 with an average pore size of 17.4 nm. The electrochemical performance of the obtained porous MnCo2O4/CoCo2O4 ellipsoids as electrode for pseudocapacitors was investigated by galvanostatic charge-discharge and cyclic voltammetry measurements in 2 M of KOH electrolyte. The composite exhibited a specific capacitance as high as 614 F g−1 at 1 A g−1 and an outstanding cycling behavior with about 77.5% capacitance retention of its initial specific capacitance after 5000 cycles at 5 A g−1. The outstanding electrochemical performances of the porous MnCo2O4/CoCo2O4 composite are mainly attributed to the combination of both types of electrode materials and its intriguing mesoporous ellipsoid-like structure, and make it one of the most promising candidate materials for the advanced energy storage devices.