▎ 摘　　要

Single porous nickel disulfide (NiS2) nanoballs and nanohybrids of NiS2 with reduced graphene oxide (NiS2/rGO) were successfully prepared by a simple hydrothermal process in the absence or presence of graphene oxide. NiS2/rGO nanocomposites exhibit remarkable electrocatalytic performance for hydrogen evolution from water splitting due to the plentiful active sites in the porous NiS2, the improved conductivity and the positive synergetic effect between NiS2 and rGO. The nanocomposites displayed superior activity for the hydrogen evolution reaction (10 mA cm(-2) vs. -200 mV, Tafel slope of 52 mV dec(-1)) and an excellent electrocatalytic stability. (C) 2016 Elsevier B.V. All rights reserved.