Silver-Intermediated Perovskite La0.9FeO3−δ toward High-Performance Cathode Catalysts for Nonaqueous Lithium–Oxygen Batteries

Development of efficient cathode catalysts is crucial for achieving high-performance rechargeable lithium–oxygen batteries. Herein, a simple one-step electrospun method was applied to obtain a silver-modified perovskite La_0.9FeO_3–δ (Ag@LFO) as an efficient cathode catalyst. The synthesized catalyst has two characteristics: first, the doping of Ag led to a tailored electronic structure including the generation of Fe⁴⁺; second, the in situ grown Ag exhibits a stronger interaction with perovskite. These two advantages result in high oxygen adsorbability and increased percentage of highly active oxygen species. Furthermore, film-like Li₂O₂ was observed during discharge on the Ag@LFO cathode, which is beneficial for decomposition during recharge, whereas Li₂O₂ generated on the LFO cathode was largely toroidal. Density functional theory calculations were used to discuss the Li₂O₂ growth mechanism. As a result, compared to La_0.9FeO_3–δ and post-loading silver-decorated La_0.9FeO_3–δ (Ag/LFO), Ag@LFO exhibits lower overpotential, improved rate-capability, higher discharge specific capacity, and especially promoted cycling performance that is triple that of LFO.