Promising Ru-Based Cathode Catalysts of Li-CO2 Batteries via Single-Atom Alloying

Abstract

The lithium-carbon dioxide (Li-CO2) battery has garnered increased attention due to its high energy density and the utilization of greenhouse gas CO2. However, the weak CO2 activation and low cathode activity hinder the development of current Li-CO2 batteries. Ru-based catalysts have become the preferred choice of catalysts in Li-CO2 batteries, in this study, the 10 single atom alloy catalysts (SAAs) composed of ruthenium (Ru) doped with 3d transition metal atoms (MRu) as cathode materials for Li-CO2 batteries were investigated by the first principles calculations. The thermodynamic stability and CO2 activation capability of pure Ru and 10 SAAs were determined by calculating the formation energy of MRu and the adsorption energy of CO2 on the catalysts. The selectivity of reaction pathways and catalytic activity of the catalysts were evaluated by thermodynamic reaction energy and kinetic reaction energy barrier. Among 10 MRu SAAs, ScRu and TiRu were screened as superior catalysts compared to Ru metal. This work offered a rational theory design for promising Ru-based catalysts.