Amorphous iridium oxide coating on TiO2 for efficient electrocatalytic oxygen evolution reaction

Ir-based electrocatalysts are commonly acknowledged as top-performing materials for water oxidation under acidic conditions. Decreasing the precious metal loading and improving the intrinsic activity of Ir sites are vital for creating effective electrocatalysts for PEMWE applications . Here, we employed a simple solvothermal method to create IrO x @TiO 2 core-shell structure electrocatalyst for efficient anodic OER in acidic environment. The obtained IrO x @TiO 2 requires an overpotential of only 227 mV to achieve 10 mA cm −2 and maintains such stability over 200 h. Furthermore the intrinsic and mass activity of IrO x @TiO 2 demonstrate a remarkable improvement of hundreds of times compared to that of IrO 2 . The core-shell structure of IrO x @TiO 2 possesses a high specific surface area , with the amorphous IrO x shell layer enhancing the catalytic activity of the Ir sites. Further structural analysis of the post-OER IrO x @TiO 2 revealed that the amorphous IrO x was effectively stabilized and high-valent IrO x generated on its surface may be more favorable for acidic water oxidation process. This study introduces a practical approach for developing high-performance, low-iridium-loading acidic OER electrocatalysts .