Oxidation effect of ammonium persulfate on the supercapacitive properties of β-Ni(OH)2 nanosheets

beta-Ni(OH)(2) nanosheets with high electrochemical performance were synthesized under in situ oxidation of ammonium persulfate by a simple precipitation method. The synthetic procedure included a precipitation step using sodium hydroxides as precipitation agent and an oxidation step using ammonium persulfate as oxidant. Due to the increased overpotential and the reduced difference between anodic and cathodic potential, the as-prepared material presented a high specific capacity of 999 C g(-1) at current density of 1.7 A g(-1), which is nearly equal to the theoretical value of beta-Ni(OH)(2). It is worth noticing that the material kept a high capacity of 509 C g(-1) at high current density of 33.9 Ag-1. Combined with the advantage of high electrochemical stability, these results suggest that the material is a highly promising candidate for application in supercapacitor. (C) 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim