Arrays of ZnSe/MoSe 2 Nanotubes with Electronic Modulation as Efficient Electrocatalysts for Hydrogen Evolution Reaction

Few‐layered MoSe 2 nanosheets have great promise as a low‐cost alternative to noble Pt‐based electrocatalysts for electrochemical hydrogen evolution reaction (HER). In this work, arrays of ZnSe/MoSe 2 nanotubes on fluorine‐doped tin oxide (FTO) glass substrates are synthesized and employed as an efficient binder‐free HER electrocatalyst for the first time. The hybrid ZnSe/MoSe 2 nanotubes have thicknesses of 3–20 nm. The growth of ZnSe layer is attributed to ion exchange with ZnO nanorods while the formation of MoSe 2 layer is resulted from chemical bath deposition. Compared with the bare MoSe 2 electrocatalyst, the hybrid ZnSe/MoSe 2 nanotube electrocatalyst exhibits striking kinetic metrics with a small Tafel slope (73 mV per decade) and a low onset potential (68 mV). Beside benefits from the nanoarray structure as binder‐free electrode as well as interlayer expansion of layered MoSe 2 , electron transfer from n‐type ZnSe to MoSe 2 induced by alignment of energy levels at heterointerface contributes to fast electron transport and active electrocatalytic behavior of MoSe 2 at the electrocatalyst–electrolyte interface, which is responsible for the significant improvement in HER performance. This work opens up a new door for developing high‐performance HER electrocatalysts by designing semiconductor heterojunction.