RuO2 clusters derived from bulk SrRuO3: Robust catalyst for oxygen evolution reaction in acid

Developing highly efficient oxygen evolution reaction (OER) catalyst for the acidic corrosive operating conditions is a challenging task. Herein, we report the synthesis of uniform RuO2 clusters with ∼ 2 nm in size via electrochemical leaching of Sr from SrRuO3 ceramic in acid. The RuO2 clusters exhibit ultrahigh OER activity with overpotential of ∼ 160 mV at 10 mA·cmgeo−2 in 1.0 M HClO4 solution for 30-h testing. The extended X-ray absorption fine structure measurement reveals enlarged Jahn-Teller distortion of RuO octahedra in the RuO2 clusters compared to its bulk counterpart. Density function theory calculations show that the enhanced Jahn-Teller distortion can improve the intrinsic OER activity of RuO2.