RuSe2/CeO2 heterostructure as a novel electrocatalyst for highly efficient alkaline hydrogen evolution

Constructing heterojunction to adjust the electronic structure of catalysts is a promising strategy for synergistically improving electrocatalytic activity. In addition, RuSe₂is recognized as an effective alternative to Pt for boosting alkaline hydrogen evolution reaction (HER) on account of its outstanding catalytic properties. Herein, novel RuSe₂/CeO₂heterojunction electrocatalysts are fabricated through hydrothermal and thermal treatment methods. The optimal 50% RuSe₂/CeO₂heterojunction electrocatalyst exhibits a low HER overpotential of 16 mV to attain 10 mA cm^-2current density and Tafel slope of 66.1 mV dec^-1for hydrogen evolution in 1.0 M KOH. At the same time, the 50% RuSe₂/CeO₂heterojunction electrocatalyst also maintains a stable HER activity for 50 h or 3000 CV cycles. The experimental results show that formation of heterogeneous interface between RuSe₂and CeO₂results in the redistribution of electrons at the RuSe₂/CeO₂interface, thereby changing the electronic structure of RuSe₂and enhancing the performance of the RuSe₂/CeO₂electrocatalyst. This work may provide a feasible way to design efficient hydrogen evolution heterojunction electrocatalysts by modulating the electronic structure in alkaline electrolytes.