Cocktail effect in high-entropy perovskite oxide for boosting alkaline oxygen evolution

Due to the cocktail effect, La0.5Sr0.5Mn0.15Fe0.15Co0.4Ni0.15Cu0.15O3 perovskite oxide hollow nanofibers exhibit excellent intrinsic activity for alkaline oxygen evolution reaction (OER) with a small overpotential of 309 mV (10 mA cm-2). Operando electrochemical Raman spectra provide evidence for the generation of crucial intermediates on specific active sites in this high-entropy oxide system. This work will guide the rational utilization of the cocktail effect in multi-site electrocatalysts. The cocktail effect in La0.5Sr0.5Mn0.15Fe0.15Co0.4Ni0.15Cu0.15O3 perovskite oxide hollow nanofibers leads to an excellent intrinsic activity for the alkaline oxygen evolution reaction (OER) with a small overpotential of 309 mV (10 mA cm-2).