The prepare of 3D porous Ni-NSAs@Ni foam was achieved by a two-step, as shown in Fig. 2. First, a precursor Ni(OH)2 was synthesized on Ni foam by utilizing a certain amount of H2NCONH2 urea, NH4F ammonium fluoride and Ni(NO3)2∙6H2O nickel (II) nitrate hexahydrate as starting materials via a hydrothermal growth method. Second, the Ni(OH)2 was transformed to Ni-NSAs@Ni foam through annealing process under ambient Ar flow with existence of EG as decomposition agent as illustrated in Fig. 1. EG was
