Modulating Electronic Structure with Copper Doping to Promote the Electrocatalytic Performance of Cobalt Disulfide in Li–O 2 Batteries

Abstract Introducing heteroatom into catalyst lattice to modulate its intrinsic electronic structure is an efficient strategy to improve the electrocatalytic performance in Li–O 2 batteries. Herein, Cu‐doped CoS 2 (Cu–CoS 2 ) nanoparticles are fabricated by a solvothermal method and evaluated as promising cathode catalysts for Li–O 2 batteries. Based on physicochemical analysis as well as density functional theory calculations, it is revealed that doping Cu heteroatom in CoS 2 lattice can increase the covalency of the CoS bond with more electron transfer from Co 3d to S 3p orbitals, thereby resulting in less electron transfer from Co 3d to O 2p orbitals of Li–O species, which can weaken the adsorption strength toward Li–O intermediates, decrease the reaction barrier, and thus improve the catalytic performance in Li–O 2 batteries. As a result, the battery using Cu–CoS 2 nanoparticles in the cathode exhibits superior kinetics, reversibility, capacity, and cycling performance, as compared to the battery based on CoS 2 catalyst. This work provides an atomic‐level insight into the rational design of transition‐metal dichalcogenide catalysts via regulating the electronic structure for high‐performance Li–O 2 batteries.