Co(OH)2/graphene sheet-on-sheet hybrid as high-performance electrochemical pseudocapacitor electrodes

A Co(OH)(2)/graphene sheet-on-sheet hybrid has been fabricated by in situ one-step hydrothermal growth for electrochemical pseudocapacitors application. The hybrid delivers a specific capacitance of 436 F g(-1) at a current density of 50 A g(-1). Besides, it can keep a specific capacitance of 651 F g(-1) after 10,000 cycles at 10 A g(-1). The excellent performance can be ascribed to the high-quality graphene matrix, regular morphology and high crystallinity of Co(OH)(2), and unique sheet-on-sheet structure of the hybrid, endowing enhanced transportation of electrons and Faradic redox reactions. The results demonstrate that the Co(OH)(2)/graphene hybrid with a sheet-on-sheet structure is promising for high-performance energy storage applications.