Zr-induced electronic perturbation of spinel Co3O4 couples activity and stability for acidic water oxidation

초록

Scaling proton exchange membrane water electrolysis (PEMWE) beyond iridium-based anodes requires earth-abundant oxides that combine high activity with acid stability, yet on transition-metal oxides catalytic turnover and cation dissolution often track a shared electronic evolution. Here we show that zirconium (Zr) doping of spinel Co3O4 breaks this coupling through a single perturbation of the lattice electronic structure. On the Zr–Co3O4 surface, Zr donates electron density to neighboring Co sites, biasing the surface cobalt toward Co2+ and redistributing the interfacial charge. The same Zr-to-Co electron transfer accelerates proton-coupled interfacial kinetics in acid and suppresses Co dissolution. Optimized Zr–Co3O4 delivers an overpotential of 307.7 mV at 10 mA cm−2 in 0.5 M H2SO4, maintains galvanostatic operation for over 150 h with strongly attenuated cobalt loss in time-resolved electrolyte monitoring, and performs as a PEMWE anode with stable operation for over 100 h at 100 and 200 mA cm−2. These results establish redox-inactive, acid-tolerant heterovalent doping as a strategy for durable non-noble acidic anodes. This journal is © the Partner Organisations, 2026.