Hollow hexagonal NiSe–Ni3Se2 anchored onto reduced graphene oxide as efficient electrocatalysts for hydrogen evolution in wide-pH range

Abstract

Abstract Integrating transition metal complexes with carbon-based materials, especially graphene, is a useful strategy for synthesizing effective hydrogen evolution catalysts. Herein, we report a design of hollow hexagonal NiSe–Ni3Se2 nanosheets grown on reduced graphene oxide (NiSe–Ni3Se2/rGO) by a simple hydrothermal method as an effective catalyst for hydrogen evolution reaction (HER) in the full pH range. In 0.5\xa0M\xa0H2SO4, the NiSe–Ni3Se2/rGO possesses 112\xa0mV to achieve 10\xa0mA\xa0cm−2 and a small Tafel slope (61\xa0mV dec−1). In 1.0\xa0M PBS and 1.0\xa0M KOH, the overpotentials are 261 and 188\xa0mV at 10\xa0mA\xa0cm−2, and Tafel slopes are 103 and 92\xa0mV dec−1, respectively. Meanwhile, it owns good cycle stability and durability over 20\xa0h in the whole pH range (0-14). In all solutions, the HER performance of NiSe–Ni3Se2/rGO is better than that of NiSe–Ni3Se2. This is because the rGO substrate accelerates the electron transfer and improves the electrical conductivity, increasing HER activity of catalyst.