Lattice and Surface Engineering of Ruthenium Nanostructures for Enhanced Hydrogen Oxidation Catalysis.

Ru has recently been considered as a promising alternative of Pt toward hydrogen oxidation reaction (HOR) due to its lower price and similar hydrogen binding energy (HBE) in comparison to Pt. Nevertheless, the catalytic performance of Ru toward HOR is far from the satisfaction of practical application. Herein, it is demonstrated that the modification of Ru multi‐layered nanosheet (MLNS) with Ni can significantly promote the HOR performance. In particular, the HOR performance is strongly related to the Ni location on the surface or in the lattice of Ru MLNS. Experimental and theoretical investigations suggest that Ni in the lattice of Ru MLNS (lattice engineering) optimizes the HBE, while Ni species on the surface (surface engineering) decrease the free energy of water formation, as a result of the significantly enhanced HOR performance. The optimal catalyst, where Ni is located both on the surface and in the lattice, displays superior alkaline HOR performance to commercial Pt/C and Ru/C. The present study not only systematically reveals the significance of Ni modification on Ru toward HOR, but also promotes the fundamental researches on catalyst design for fuel cell reactions and beyond. [ABSTRACT FROM AUTHOR]