Highly Efficient Oxygen-Modulated Ru-Based HER Electrocatalyst in a Wide pH Range

Graphical Boosting HER stability : The Ru-MC prepared by a special synthesis method can greatly improve the utilization of Ru; the strong interaction between Ru and O modulates the electronic structure of Ru nanoparticles (NP) and prevents Ru NPs from aggregation to boost HER stability. The Ru(3 mL)-MC exhibits high HER performance with overpotential of 27 and 40 mV at benchmark of 10 mA cm −2 both in alkaline and acidic solutions. Crystallized Ruthenium (Ru) metal with high hydrogen production activity is extremely unstable. Herein, we report an efficient and durable hydrogen evolution reaction (HER) electrocatalyst Ru-MC (mesoporous carbon) synthesized by a special method, in which Ru 3+ is added after the formation of spherical MC, leading to only a small amount of Ru being embedded and the vast majority being evenly distributed on the MC surface. The dispersed Ru nanoparticles not only prevent them from aggregation to greatly improve their stability (both over 160 hours in acidic and alkaline solutions), but also provide outstanding intrinsic catalytic activity because oxygen regulates the electronic structure of Ru nanoparticles. The as-synthesized catalyst only needs an overpotential of 27 and 40 mV to deliver 10 mA cm −2 in 1.0 M KOH and 0.5 M H 2 SO 4 . The present work provides guidance for the design of efficient and stable Ru-based HER electrocatalysts used in a wide pH range.