Ni(OH)2/RGO nanosheets constituted 3D structure for high-performance supercapacitors

Abstract

Ni(OH)2/reduced graphene oxide (RGO) nanosheets constituted 3D structure have been successfully prepared via a facile two-step method. Through this method, Ni(OH)2 can uniformly grow on both side of RGO nanosheets and the RGO nanosheets are partially overlapped, thereby forming a 3D structure. The Ni(OH)2/RGO composite delivers much higher specific capacitance and improved rate capability than the pure Ni(OH)2 sample and the Ni(OH)2–RGO mixture. A specific capacitance up to 1143 F g−1 at 1 A g−1 is attained, 64 % of which can still be retained after 20 times increase in current density. In addition, excellent cycling stability can also be obtained, and 97 % of the capacitance can still be retained after 1500 charge and discharge cycles. Ni(OH)2/RGO nanosheets constituted 3D structure have been successfully prepared, which show superior specific capacitance with improved rate capability and long cycling stability.