Ultrafast Microwave Quasi‐Solid‐State Construction of Os‐OsP₂ with Enhanced Interfacial Spillover for Seawater‐Based Anion Exchange Membrane Electrolyzers
Xiaowei Fu, Xingchao Zang, Jinxiao Gao, Hongdong Li, Weiping Xiao, Yingxia Zong, Guangying Fu, Jinsong Wang, Tianyi Ma, Wei Jin, Zexing Wu, Lei Wang
Abstract
Abstract Developing cost‐effective hydrogen evolution reactions (HER) catalysts to replace Pt/C in alkaline seawater media remains a critical challenge. Therefore, the osmium‐osmium phosphide (Os‐OsP 2 ) catalyst is reported with a heterogeneous junction through ultrafast (20 s) microwave quasi‐solid approach for seawater‐splitting under industrial‐grade current density. Experimental and theoretical analysis reveal that the Os‐OsP₂ interface optimizes electronic structure: osmium (Os) sites accelerate water dissociation by lowering the d‐band center, while OsP₂ promotes hydrogen desorption via interfacial spillover, collectively reducing the HER energy barrier. In addition, the catalyst requires only 1.74 V to reach 1 A cm −2 and owns high price activity in the anion exchange membrane water electrolyzer, surpassing commercial Pt/C by 23% in efficiency under identical conditions. Furthermore, it exhibits robust HER activity across a wide pH range and exceptional durability over 100 h in alkaline seawater. Economic evaluation highlights its superior cost activity (85.6 A dollar⁻¹), 90‐fold higher than Pt/C, with hydrogen production costs ($0.86 GGE⁻¹) undercutting the U.S. DOE target. This study provides feasible guidance for the development of high‐performance, cost‐effective catalysts for scalable hydrogen production from seawater.