Construction of MoO₂/MoS₂ heterojunctions on carbon nanotubes as high-efficiency electrocatalysts for H₂ production

In this work, we developed an evaporation crystallization method combined with a hydrogen thermal reduction method to construct a MoO2/MoS2 heterojunction on carbon nanotubes (denoted as MoO2/MoS2@CNT) for hydrogen evolution. In the HER process, the resultant MoO2/MoS2@CNT exhibited excellent catalytic activity, which featured a small overpotential of 158 mV at a current density of 10 mA cm(-2) along with a Tafel slope of 70 mV dec(-1) as well as excellent stability in 0.5 M H2SO4. Experimental findings and theoretical calculations show that the excellent electrocatalytic performance is mainly due to the strong interaction between MoO2 and MoS2, which can help to effectively optimize the electronic structure, lower the catalytic energy barrier, and thereby enhance the HER activity. This work provides an effective strategy for constructing a heterojunction to regulate the electron structure, which will generate more inspiration for designing efficient electrocatalysts.