In situ synthesis of two-dimensional Co2+-doped β-Ni(OH)2 using nickel complex as template for application in supercapacitors

Abstract

2D nanostructured Co2+-doped β-Ni(OH)2 as electrode material for application in redox-type supercapacitors was synthesized by a strategy of nickel complex template. The 2D Co2+-doped β-Ni(OH)2 was produced by the in situ reaction of 2D Co2+-doped template in strong alkaline electrolyte solution during electrochemical measurement. Due to the large interface and the promoted conductivity induced by Co2+ doping, the Co2+-doped β-Ni(OH)2 exhibited high electrochemical performance. It had high specific capacitance of about 2100 F g–1 at low current density of ~2 A g−1. It also exhibited excellent high rate performance (1259 F g–1 at high current density of 41.7 A g−1), much higher than the undoped sample. The results in this work indicated that the Co2+-doped β-Ni(OH)2 could be used as an effective electrode material in redox supercapacitors.