Highly active and stable amorphous IrO_x/CeO₂ nanowires for acidic oxygen evolution

Development of highly active and durable electrocatalysts for acidic oxygen evolution reaction (OER) remains an unresolved grand challenge. Here, we reported the amorphous IrO_x/CeO₂ nanowires as highly active and acid-stable OER catalysts through a facile electro-spinning/calcination approach. The amorphous catalysts delivered a high mass activity of 167 A g_Ir⁻¹ at 1.51 V, a low overpotential of 220 mV at 10 mA cm⁻², and a stable performance for 300 h of continuous operation in acid. As revealed by complementary experimental and theoretical calculation results, the intimate nanoscale feature of IrO_x/CeO₂ creates abundant binary interfaces, at which CeO₂ as an electron buffer regulates the adsorption of oxygen intermediates, lowers the activation barrier of OER, and suppresses the over-oxidation and dissolution of Ir, thereby significantly enhancing the OER activity and stability. This work provides a new strategy for designing highly active and acid-resistant OER catalysts.