The oxygen evolution reaction (OER) in acidic media is critical for acidic water electrolysis, electrochemical CO 2 reduction, nitrate reduction, etc. However, its harsh corrosive and oxidative environment imposes severe demands on catalysts. Ru‐based catalysts offer high activity and low cost, but their poor stability in acidic media remains a key obstacle to practical application. Herein, we report a robust composite catalyst of cobalt‐doped manganese oxide ((Co 0.08 Mn 0.92 ) 3 O 4 )‐supported RuO 2 on a titanium substrate for high activity and stability in acidic media. (Co 0.08 Mn 0.92 ) 3 O 4 is uniformly immobilized on a titanium substrate via a sol–gel method, followed by a hydrothermal and calcination treatment to uniformly hydrolyze RuCl 3 and convert it into RuO 2 within the loose and porous (Co 0.08 Mn 0.92 ) 3 O 4 . The Co doping induces the strong electron interaction of Co, Mn, and Ru, creating a highly active RuO 2 /(Co 0.08 Mn 0.92 ) 3 O 4 interface. The optimized catalyst requires only 185 mV overpotential to achieve a current density of 10 mA cm −2 , with a stability of more than 1000 h at 100 mA cm −2 in 0.5 M H 2 SO 4 . In situ Raman spectroscopy experiments confirm that the doping of Co significantly enhances the stability of Mn 3 O 4 , while (Co 0.08 Mn 0.92 ) 3 O 4 suppresses the participation of lattice oxygen and enhances the stability of active Ru species.
Yang et al. (Mon,) studied this question.