Porous Perovskite La 0.6 Sr 0.4 Co 0.8 Mn 0.2 O 3 Nanofibers Loaded with RuO 2 Nanosheets as an Efficient and Durable Bifunctional Catalyst for Rechargeable Li–O 2 Batteries

The design and synthesis of efficient electrocatalysts are important for electrochemical energy conversion and storage technologies. Poor electrocatalytic activities of the cathode catalysts toward both the oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) are still two major challenges facing Li–O 2 batteries. Here, we report ultralong porous perovskite La 0.6 Sr 0.4 Co 0.8 Mn 0.2 O 3 nanofibers (LSCM NFs) loaded with RuO 2 nanosheets (RuO 2 @LSCM NFs) used as a promising catalyst for Li–O 2 batteries. The LSCM nanofibers were synthesized via an electrospinning technique followed by heat treatment. RuO 2 nanosheets were loaded by a wet impregnation method. In comparison with that of the pristine LSCM NFs, the cell with RuO 2 @LSCM NFs catalyst exhibits good performances toward the ORR and OER with a higher specific discharge capacity (12741.7 mA h g –1 ), improved cyclability, and rate capability as well as low voltage gap. Moreover, the results of LSV indicate that LSCM NFs can efficiently catalyze the decomposition of the reaction side product Li 2 CO 3 while RuO 2 @LSCM NFs are capable of decomposing LiOH. The enhanced cell performances are attributed to the merits of high catalytic activity and the porous structure of the RuO 2 @LSCM NF catalyst.