Controlled synthesis of ultrasmall RuP₂ particles on N,P-codoped carbon as superior pH-wide electrocatalyst for hydrogen evolution

Electrocatalytic hydrogen evolution reaction (HER) is a highly potential strategy to massively produce green hydrogen fuels. However, the employment of costly Pt-based electrocatalyst in the cathode of electrolyzer greatly hampers the development of hydrogen economy. Ruthenium phosphide catalysts have recently drawn wide attention due to the Pt-like activity but relatively lower cost. Herein, a facile strategy was proposed for the controlled preparation of the ultrasmall RuP₂ nanoparticles on N,P-codoped carbon from common precursors of Ru (II) complex and phytic acid. By taking advantage of simple mixing and pyrolysis, the as-synthesized RuP₂ nanoparticles were uniformly embedded onto the N,P-codoped carbon nanosheet. The composite catalyst shows better activity than Pt/C for alkaline HER and comparable activity for acidic and neutral HER. The superior activity can be ascribed to the ultrasmall-size and efficient RuP₂ together with good mass and charge transfer ability assured by N,P-codoped carbon support. The advantages including low-cost and simple synthesis in this work present an encouraging substitute to replace commercial Pt/C for hydrogen-related practical applications.