Cu Atom Regulated AuPtCu@T‐Cu x S Janus Heterostructure Electrocatalyst for High‐Performance Lithium‐Oxygen Batteries

Abstract The Janus heterostructure containing two disparate functional components can be well adopted as electrocatalyst for lithium‐oxygen batteries (LOBs), whose asymmetrical discharge/charge electrochemical process and low oxygen reduction and oxygen evolution reaction (ORR/OER) kinetics result in poor round‐trip efficiency. Herein, an efficient copper atom modulation strategy is developed to construct well‐designed Cu‐deficient T‐Cu x S nanoparticles (Cu 1.75 S treated at high temperature), paired with AuPtCu nanoalloy (AuPtCu@T‐Cu x S), serving as bifunctional cathode electrocatalysts to accelerate ORR/OER kinetics of LOBs. The abundant coordination unsaturated sites on the surface of T‐Cu x S can be viewed as the anchoring center of AuPt, and also can be efficient catalytic sites for the ORR/OER kinetics. The internal electric field modulates the electronic structure and d‐band center of the Cu and Pt atoms, optimizes the interaction between the AuPtCu@T‐Cu x S and the intermediate LiO 2 , regulating the growth mode of the Li 2 O 2 . As expected, LOBs based on AuPtCu@T‐Cu x S catalyst delivers a minimal overpotential (0.56 V) and long‐term cyclability (590 cycles, 500 mA g −1 ) at 1000 mAh g −1 , exceeding most state‐of‐the‐art Janus electrocatalysts. This work affords significant insights for atomic and electronic structure optimization of Janus heterostructures for LOBs.