Abstract: Single atom catalysts (SACs) are efficient electrocatalysts for catalyzing the oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) in lithium-oxygen batteries (LOBs). Our method is to study the origin of reactivity for a series of 17 transition metals supported on nitrogen-doped graphene, denoted SACs using Quantum Mechanics methods. Based on Gibbs free energy calculations, Zn-SAC performs the highest electrochemical activity among 17 SACs investigated. Machine learning (ML) is developed an intrinsic descriptor ?, that correlates the catalytic activity with electronic and chemical properties of the catalytic centers at the M-N4 active site on graphene surface. A linear relationship between ? and the catalytic activity that provides guidance for designing efficient SACs for electrocatalysis in LOBs. Zn-SAC is synthesized through chemical vapor deposition (CVD) process, which shows more stable cyclability and exhibits smaller reaction overpotentials, verifying the simulation results.

Abstract: An anode materials VSe2/Zn, including a functional Vanadium diselenide (VSe2) with graphene support composite coated on the Zn metal with super ion conductivity, is used in a zinc ions battery. The synthesis process includes polymerization and chemical vapor deposition process for selenization with selenium powder.