Nitrogen-doped RuS 2 nanoparticles containing in situ reduced Ru as an efficient electrocatalyst for hydrogen evolution.

The production of hydrogen via water electrolysis brings hope for the realization of hydrogen economy, but there is still a lack of highly efficient and appropriate electrocatalysts for the generation of hydrogen in practical applications. In particular, reasonable construction and feasible preparation strategies are the essential requirements for excellent electrocatalysts. Herein, the heterostructures of N-RuS 2 /Ru nanoparticles were designed by annealing the RuS 2 nanoparticles in ammonia. By introducing a nitrogen dopant and single-phase Ru metal simultaneously, high-efficiency electrocatalytic performance for hydrogen evolution reaction (HER) was implemented, where the electrocatalyst of N-RuS 2 /Ru exhibited a low onset overpotential of 76 mV and small overpotential of 120 mV at 10 mA cm -2 in an acidic electrolyte. Besides, it displayed a low Tafel slope of 53 mV dec -1 , a small interface charge transfer resistance, and long-time stability and durability, suggesting its remarkable properties as a promising HER electrocatalyst candidate.