High-Performance Ru2P Anodic Catalyst for Alkaline Polymer Electrolyte Fuel Cells

Abstract

Exploring efficient and economical electrocatalysts and understanding the mechanism for alkaline hydrogen oxidation reaction (HOR) are crucial to facilitate the development of alkaline polymer electrolyte fuel cells (APEFCs). Herein, Ru2P was synthesized and used as an anodic HOR electrocatalyst for APEFC, achieving a peak power density of 1.3 W cm-2, the highest value among Pt-free anode electrocatalysts reported under the same conditions. Fromthe density functional theory (DFT) calculations and experimental results, it was found that besides the optimized hydrogen binding energy, the enhanced adsorption strength of oxygenated species (OH*) and the reduced work function of Ru2P contributed to the enhanced HOR performance. The normalized exchange current densities of Ru2P/C were 0.37 mA cmECSA -2 and 0.27 mA μgRu -1, respectively, both approximately three times higher than those of Ru when conducted in the rotating disk electrode (RDE) system. Our work provides a new pathway for exploring highly active Pt-free HOR electrocatalysts and expanding the family of anodic electrocatalysts for APEFCs.