The graphene-supported Lanthanum oxide cluster as efficient bifunctional electrocatalyst for oxygen reaction

The development of bifunctional oxygen electrode electrocatalysis for both the oxygen reduction reaction (ORR) and the oxygen evolution reaction (OER) plays a vital role in the solution of the energy crisis as well as the environmental pollution. The purpose of this paper is to investigate the potential of graphene-supported lanthanum oxide clusters (La2O3-Gra) as a bifunctional electrocatalyst; the results show that the optimal catalytic site (up-down1) of the most stable configuration (O-Gra-1) modified by OH group shows outstanding bifunctional catalytic activity with ηORR of 0.51 V and ηOER of 0.52 V, which can be compared to the commercial Pt-based ORR catalysts and the Ru/Ir-oxides OER catalysts. Furthermore, there is a strong scale-dependent relationship between the adsorption free energy (ΔGads) of reaction intermediates, resulting in volcano plots between the catalytic activity and ΔGads, which provides a valuable description for future performance prediction of structurally similar catalysts.