Transition Metal-Promoted VC(001) for Overall Water Splitting and Oxygen Reduction
Rong Zhao, Chenfan Yang, Qin Zhang, Hui Xiang, Yanjun Li, Xuanke Li
Abstract
The development of highly efficient, stable, and low-cost electrocatalysts for renewable energy remains a significant challenge. Transition metal carbide (TMC)-based catalysts have been reported to feature high activity and outstanding stability in both the hydrogen evolution reaction (HER) and oxygen evolution reaction (OER). Here, density functional theory computations are carried out to investigate the potential performance of transition metal-doped VC(001) systems on the HER, OER, and oxygen reduction reaction (ORR). The results reveal that the introduction of transition metals not only greatly enhances the weak binding between hydrogen and the surface, but also modulates the interaction strength of the OER/ORR adsorption intermediates. More importantly, Ir-doped VC(001) presents promising trifunctional electrocatalytic activity with low overpotentials of 0.10, 0.56, and 0.52 V for the HER, OER, and ORR, respectively. The Pt-doped VC(001) is expected to be a promising bifunctional electrocatalyst for overall water splitting (0.16 V for the HER, 0.58 V for the OER). The Fermi-abundance model is used to better understand the origin of the HER, OER, and ORR activities of the TM-doped VC(001) structures. In this study, we developed a Fermi-abundance model that provides new possibilities for the rational design of multifunctional electrocatalysts for renewable energy conversion and storage as well as the application of TMCs.