Silver-Intermediated Perovskite La 0.9 FeO 3−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 0.9 FeO 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 Fe 4+; 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. Therefore, film-like Li 2 O 2 was observed during discharge on the Ag@LFO cathode, which is beneficial for decomposition during recharge, whereas Li 2 O 2 generated on the LFO cathode was largely toroidal. Density functional theory calculations were used to discuss the Li 2 O 2 growth mechanism. As a result, compared to La 0.9 FeO 3−δ and post-loading silver-decorated La 0.9 FeO 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.