Phosphorus-Induced Activation of Ruthenium for Boosting Hydrogen Oxidation and Evolution Electrocatalysis

Abstract

Developing efficient electrocatalysts toward alkaline hydrogen oxidation and evolution reactions (HOR/HER) and fundamental understanding their catalytic mechanisms are highly desirable with the rapid development of hydrogen economy. Here, we report that the surface electronic structure of ruthenium (Ru) can be effectively modulated through phosphorus (P) doping to produce significantly enhanced catalytic HOR and HER performance in alkaline electrolyte. By controlling the amount of P, the resulted P–Ru/C exhibits outstanding catalytic activity, achieving a normalized exchange current density of 0.72 mA cm–2 and mass activity of 0.43 mA μg–1, approximately 5 and 3.5 times higher than those of Ru/C, respectively, and even 2 times higher than that of Pt/C (commercial 20 wt %) for HOR. Moreover, sixfold enhancement compared with Ru/C in the HER can be achieved from P–Ru/C. Experimental and density functional theory results indicate that electronic manipulation through P-doping is beneficial to the prominent HOR/HER performance and enhanced kinetics.