Heteroatom Doping-Induced Defected Co₃O₄ Electrode for High-Performance Lithium Oxygen Battery

Development of electrocatalysts with high activity and stability is crucial for advanced lithium oxygen batteries due to their sluggish reaction kinetics and undesirable parasitic reactions. Herein, we demonstrate that heteroatom doping is a feasible strategy to trigger oxygen vacancies, and remarkably enhance the conductivity and catalytic activity of the Co₃O₄ electrocatalyst. The optimized Co₃O₄ cathode with abundant oxygen vacancies regulates the geometric morphology of the discharge product Li₂O₂, which accelerates the oxygen reduction/evolution reaction kinetics notably and lowers the redox overpotential. Density functional theory calculations reveal that intrinsic LiO₂-adsorption ability on the Co₃O₄ surface is dramatically strengthened after heteroatom doping, thus fundamentally modulating the growth route of Li₂O₂ and suppressing the parasitic reactions caused by LiO₂. In particular, a phosphorus-doped Co₃O₄ cathode exhibits a decreased polarization potential (1.2 V), large initial discharge capacity (7690 mAh g^–1 at 100 mA g^–1), and good cyclability (90 cycles at 100 mA g^–1). This work provides insight into the vital role of heteroatom doping and oxygen vacancies in tailoring the morphology of Li₂O₂ and suppressing side reactions, and provides inspiration for cathode catalyst design in lithium oxygen batteries.