Core-shell structured MoS2/Ni9S8 electrocatalysts for high performance hydrogen and oxygen evolution reactions

Abstract It is well known that traditional electrocatalysts usually show high overpotential and poor cycling stability. Therefore, it is crucial to design high efficient bifunctional electrocatalysts for sustainable energy conversion. In this study, we synthesize several heterostructured MoS2 nanomaterials by a simple one-pot hydrothermal approach. MoS2 nanosheets are anchored on the surface of Ni9S8 nanorods to form a novel 3D structure. This high active heterogeneous interface benefit to exposing many active sites and facilitating the charge transfer along the Ni9S8 nanorods vertically grown on conductive nickel foam. During water splitting process, the MoS2/Ni9S8 sample shows a low overpotential (hydrogen evolution reaction, HER) at 10 mA cm−2 and (oxygen evolution reaction, OER) at 50 mA cm−2. Moreover, the as-assembled cell delivers a voltage of 1.72 V at 50 mA cm−2.