Ru2P/Ir2P Heterostructure Promotes Hydrogen Spillover for Efficient Alkaline Hydrogen Evolution Reaction.

Efficient and durable electrocatalysts toward alkaline hydrogen evolution reaction (HER) are of great significance for the widespread application of anion‐exchange membrane water electrolyzer (AEMWE). Numerous single‐phase catalysts, such as Ru2P, have been explored as efficient HER catalysts; however, many have failed to overcome the inherent sluggish kinetics of the two separate steps involved in the alkaline HER: water dissociation and hydrogen production. In this study, density functional theory calculations are conducted to identify promising combinations of Ir2P and Ru2P materials that promote fast cascade water dissociation and H2 production via kinetically favorable hydrogen spillover from the Ru2P surface to the adjacent Ir2P. An unprecedented construction of Ir2P cluster‐decorated Ru2P hollow nanotubes (<italic>c</italic>‐RP/IP HNTs), which feature a cooperative heterostructural synergy are developed. This configuration shows greater performance than commercial Pt/C, achieving an overpotential of 23.2 mV at 10 mA cm−2 and maintaining long‐term stability for 55 h in half‐cell tests. Furthermore, the practical AEMWE test, incorporating <italic>c</italic>‐RP/IP HNTs, demonstrated a remarkable single‐cell performance of 12.23 A cm−2 at 2.0 V and operated stably under 1.0 A cm−2 for over 250 h. This surpasses that of the state‐of‐the‐art proton‐exchange membrane WE. [ABSTRACT FROM AUTHOR]