Re/Ag Comodulated MnO ₂ for Highly Active and Durable Oxygen Evolution in Acidic Solution

Rutile-type MnO2 for the oxygen evolution reaction (OER) in acidic media suffers from poor electrocatalytic activity and low durability owing to the poor conductivity and peroxidation. Here, a facile pyrolysis method is employed to successfully fabricate rhenium (Re)- and silver (Ag)-incorporated MnO2 (ReAg-MnO2) loaded on a substrate of a corrosion-resistant Ti plate with an interlayer of Sb-doped SnO2 (Sb–SnO2). The ReAg-MnO2 anode achieves a low overpotential of 315 mV at a current density of 10 mA cm–2 and a small Tafel slope of 55.7 mV dec–1, displaying an ultrahigh durability of over 500 h at a large current density of 200 mA cm–2. The incorporation of Re and Ag in the MnO2 bulk reasonably modulates the electronic structure and favorably suppresses the peroxidation of Mn sites during the acidic OER. This work provides a new strategy for the practical application of nonprecious MnO2-based electrocatalysts in the electrochemical industry for acidic OER.