Controllable fabrication of uniform ruthenium phosphide nanocrystals for the hydrogen evolution reaction

Uniform ruthenium phosphide (Ru2P and RuP) nanocrystals grown in situ on N- and P-codoped graphene were obtained by pyrolyzing tris(triphenylphosphine) ruthenium(ii) chloride (TPP-Ru) with pyritic acid (PA). Interestingly, Ru2P and RuP can be controllably prepared by varying the molar ratio of PA to TPP-Ru. As an efficient electrocatalyst for the hydrogen evolution reaction (HER), Ru2P exhibited a better performance than RuP in alkaline medium.