Coupling electron-buffered dual single-atom pairs to unlock exceptional industrial-grade PEM water electrolysis

Abstract

Single-atom catalysts represent a promising path for reducing noble-metal dependency in a proton exchange membrane water electrolyzer (PEMWE), yet insufficient industrial-level performance limits their application. Herein, we report a flash Joule heating-synthesized spinel Co3O4 doped with paired, acid-resistant Ir and highly active Ru single atoms (IrRu/Co3O4) for an efficient acidic oxygen evolution reaction (OER). Experimental and theoretical analyses reveal that the asymmetric Ir–O–Ru dual-site coordination facilitates direct ∗O–∗O coupling to accelerate reaction kinetics. Moreover, the electron-buffered Ir-Ru pairs exhibit a stabilized higher Ir valence and suppressed Ru oxidation states for balanced activity and stability, which endow IrRu/Co3O4 with an outstanding mass activity (10,680 A gIr + Ru−1) and turnover frequency (3.95 s−1) at 1.48 V. The assembled PEMWE achieves excellent durability over 1,000 h at 2.0 A cm−2 with minimal decay (0.028 mV h−1). This work establishes the electron-buffer concept as an effective strategy for designing industrial-level anodes via dual single-atom engineering.