Synthesis of Ru-Doped VN by a Soft-Urea Pathway as an Efficient Catalyst for Hydrogen Evolution

摘要

Unraveling the effect of metal doping on the intrinsic activity of metal nitride remains a grand challenge. Herein, Ru (Rh)-doped vanadium nitride are successfully synthesized via a simple soft-urea pathway. In comparison, the Ru-doped VN electrocatalyst exhibits much better HER performance than Rh-doped VN electrocatalysts. The optimal Ru-VN catalyst delivers a low overpotential of 134 (144) mV at current density of 10 mA cm(-2), and a low Tafel slope of 35 (73) mV dec(-1) in acidic (alkaline) condition. Such excellent performance can be attributed to the unique synergetic effect between Ru and VN. Moreover, moderate Ru dopant can effectively promote the HER kinetics of VN, resulting in mechanism transformation of hydrogen evolution from Volmer-Heyrovsky to Volmer-Tafel route, especially in acidic condition. This simple and facile strategy can be utilized to fabricate a series of Ru-doped nitrides, which can be applied in energy conversion fields.