Identifying efficient two-dimensional transition metal oxide cathodes for non-aqueous lithium‒oxygen batteries using work function as a simple descriptor

Abstract

The energy density of non-aqueous lithium‒oxygen battery (LOB) is far below its theoretical value, which is attributable to the slow kinetics of the redox reaction at the cathode. To address this challenge, we employ first-principles calculations to explore the potential application of 356 kinds of two-dimensional (2D) transition metal oxides (TMOs) as bifunctional oxygen reduction/evolution reaction (ORR/OER) electrocatalysts for non-aqueous LOBs. We introduce the work function of 2D TMOs as a key descriptor for the first time, which is instrumental in evaluating the LiO2 adsorption energy and the overall catalytic properties. This enables approach facilitates the rapid screening of materials such as 1T-VO2, W2O4, Mo2O4, and Re2O4, highlighting their excellent activities in ORR/OER catalysis. This work emphasizes the critical role of the work function in the catalytic ORR/OER on 2D TMOs, which is intended to provide inspiration for the future development of LOBs.