Defect Engineering of RuO2 Aerogel for Efficient Acidic Water Oxidation

The development of renewable energy conversion devices heavily relies on the design of high-performance electrocatalysts for water electrolysis systems. In this study, a Se-doped RuO2 aerogel (Se-RuO2 aerogel) with abundant defects is prepared as an excellent oxygen evolution reaction (OER) electrocatalyst in acidic media. The Se-RuO2 aerogel exhibits a remarkably low overpotential of 166 mV at a current density of 10 mA cm–2 and long-term stability of up to 48 h. Concurrently, detailed in situ experiments demonstrate that the Se-RuO2 aerogel can maintain excellent stability during the OER process, for their reaction path follows a more stable adsorption evolution mechanism. Therefore, it can operate for 100 h at a current density of 100 mA cm–2 when assembled as an anode catalyst in a polymer electrolyte membrane (PEM) electrolyzer. This work provides a new vision for the design of high-performance electrocatalysts based on aerogel with defect engineering.