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

摘要

Development of highly active and durable electrocatalysts for acidic oxygen evolution reaction (OER) remains an unresolved grand challenge. Here, we reported the amorphous IrOx/CeO2 nanowires as highly active and acidstable OER catalysts through a facile electro-spinning/calcination approach. The amorphous catalysts delivered a high mass activity of 167 A(gIr)(-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 IrOx/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.

关键词