Significantly enhanced oxygen evolution reaction performance by tuning surface states of Co through Cu modification in alloy structure

Abstract The design of high efficiency, low cost and abundant sources electrocatalysts for oxygen evolution reaction (OER) has attracted more and more attention, because of the depletion of precious and rare metals. Herein, we reported a highly active Co0.7Cu0.3 alloy, which screening from a series of CoxCu1-x alloys (x = 0.1–0.9) via surface composition controlling and electron state modification. Compared with the Co, other CoxCu1-x alloys, as well as commercial RuO2/IrO2, the Co0.7Cu0.3 catalyst exhibited very high activity in electrocatalytic O2 production from alkaline solution (∼207 mV overpotential). Meanwhile the Co0.7Cu0.3 catalyst exhibited excellent durability for OER, after 72,000 s operation, the attenuation rate of Co0.7Cu0.3 catalyst is lower than ∼ 20%. The high catalytic activity of Co0.7Cu0.3 is attributed to positive shift of d-band center and surface species of Co0.7Cu0.3 alloy which facilitates oxygen-containing species (OCS) formation (*H2O2, *OOH, *OH) and electron transfer. This method of improving the catalytic performance by adjusting the alloy composition to achieve the microscopic electronic perturbation effect is expected to attract attention in the later research.