Self-supported iridium-ruthenium oxides catalysts with enriched phase interfaces for boosting oxygen evolution reaction in acid

Developing highly efficient low-noble-metal loading electrocatalysts for acidic oxygen evolution reaction (OER) remains a great challenge. Herein, we developed a novel self-supported IrmRunOx/Ti electrode exhibiting an amorphous film encapsulated with a small number of crystalline nanoparticles for efficient acidic OER. The as-synthesized Ir0.95Ru0.05Ox/Ti electrode exhibits an excellent OER performance with an overpotential of 200 mV at 10 mA cm−2, a Tafel slope of 46.8 mV dec-1, and robust stability of 192 h in 0.1 M HClO4. The enriched heterogeneous interfaces between the amorphous phase and crystalline phase enhance the stability and activity of the solid solution oxides. The high density of oxygen vacancies on the surface, together with the strong electronic interaction contribute to boosting the OER. This work provides some valuable insights into developing efficient Ir-based catalysts for acidic water splitting.