Oxygen spillover from RuO 2 to MoO 3 enhances the activity and durability of RuO 2 for acidic oxygen evolution

Oxygen spillover strategy of *O intermediate from RuO 2 to MoO 3 within RuO 2 /MoO 3 catalysts can significantly suppress over-oxidation and dissolution of RuO 2 , which contributes to both high activity and durability for oxygen evolution in 0.5 M H 2 SO 4 .