A Novel Method to Prepare Flexible 3D NiO Nanosheets Electrodes for Alkaline Rechargeable Ni−Zn Batteries

Abstract The combination of excellent mechanical properties and electrochemical performances of Ni‐based cathodes is fascinating and challenging for Ni−Zn batteries. Herein, a novel and eco‐friendly strategy of the cycle of Ni 2+ hydrolysis and H + etching process at Ni/solution interface under moderate temperature is demonstrated to synthesize the three‐dimensional NiO nanosheets array supported on pressed Ni foam electrode (denoted as NiO/PNF). The as‐prepared NiO/PNF electrode exhibits outstanding mechanical flexibility and stability with a capacity of 5.08 mAh cm −3 . The assembled NiO/PNF||Zn battery presents peak energy and power densities up to 5.2 mW h cm −3 and 1944.4 mW cm −3 .