In situ growth of Ni0·85Se on graphene as a robust electrocatalyst for hydrogen evolution reaction.

Seeking the efficient and robust electrocatalysts necessarily enhances performance of hydrogen evolution reaction (HER). Increasing the surface active sites is a means to improve the performance. Herein, we use the Ni 0·85 Se anchored on reduction of graphene oxide (Ni 0·85 Se/rGO) hybrid material skillfully established by one-step facile hydrothermal method as a robust and stable electrocatalyst applying to hydrogen evolution reaction (HER). In terms of morphology, Ni 0·85 Se nanospheres composed of many nanosheets are uniformly distributed on the graphene sheet layer. We also detailedly analyze its properties. Based on the interaction between Ni 0·85 Se and rGO, and the roles of graphene are as a substrate to heighten conductivity, possesses more active surface area by limiting growth of Ni 0·85 Se, and increases dispersion for exposing more active surface area and enlarge ion/electron transfer rate. In HER, the Ni 0·85 Se/rGO catalyst displays the overpotential of 128 mV with a common current density of 10 mA cm−2, a small Tafel slope of 91 mV dec−1, an extremely low onset potential of 37 mV, outstanding stability that a high current retention of 97.7% after 1000 cycles and well long-term stability for 18 h, outperforming the capability of Ni 0·85 Se nanospheres in alkaline solution for HER. The above results indicate that the Ni 0·85 Se/rGO hybrid material is a good HER ability and non-noble metal electrocatalyst has potential value in HER. • The Ni 0.85 Se nanospheres uniformly decorate the rGO sheets. • The Ni 0.85 Se/rGO electrocatalyst possesses more active surface area. • The stability of the composites can reach 97.7%. • The hybrid material exhibits superior performance for HER. [ABSTRACT FROM AUTHOR]