Cr dopant mediates hydroxyl spillover on RuO₂ for high-efficiency proton exchange membrane electrolysis.

ABSTRACT: Simultaneously improving the activity and stability of catalysts for anodic oxygen evolution reaction (OER) in proton exchange membrane water electrolysis (PEMWE) remains a notable challenge. Here, we report a chromium-doped ruthenium dioxide with oxygen vacancies, termed Cr_0.2Ru_0.8O_2-x, that drives OER with an overpotential of 170 mV at 10 mA cm^-2 and operates stably over 2000 h in acidic media. Experimental and theoretical studies show that the synergy of Cr dopant and oxygen vacancy induces an unconventional dopant-mediated hydroxyl spillover mechanism. Such dynamic hydroxyl spillover from Cr dopant to Ru active site changes the rate-determining step from OOH* formation to O₂ formation and thus greatly improves the OER performance.

SUBMITTER: Shen Y 

PROVIDER: S-EPMC11385839 | biostudies-literature | 2024 Sep

REPOSITORIES: biostudies-literature