Co2P decorated Co3O4 nanocomposites supported on carbon cloth with enhanced electrochemical performance for asymmetric supercapacitors

Abstract

Co₃O₄ has attracted tremendous attention for the application in supercapacitors, but the design and fabrication of Co-based electrodes in novel construction are still a challenge. An effective strategy is successfully demonstrated to promote electrochemical performance by the combination of Co₃O₄ with highly conductive transition metal phosphides Co₂P to form a composite electrode. The as-synthesized Co₂P decorated Co₃O₄ nanocomposites (Co₂P@Co₃O₄) exhibit an enhanced areal specific capacitance of 0.504 C cm⁻² at 2 mA cm⁻² and the capacitance is increased by 49.2% compared to that of the pure Co₃O₄ electrode. Furthermore, an asymmetric supercapacitor by the assembly of a Co₂P@Co₃O₄ cathode and a porous carbon cloth (PCC) anode exhibits a maximum volumetric capacitance of 5 C cm⁻³ and excellent cycling performance (only 6% capacitance loss after 8000 cycles) at a reversible working voltage of 1.6 V.