Kinetic insight into perovskite La0.8Sr0.2VO₃ nanofibers as an efficient electrocatalytic cathode for high‐rate LiO₂ batteries

Efficient electrocatalysis at the cathode is essential for overcoming the limitations of LiO 2 batteries such as poor stability and low rate capability. Herein, we systematically studied the kinetic behavior of a LiO 2 battery comprising perovskite La 0.8 Sr 0.2 VO 3 nanofibers formed by partial Sr‐cation doping and V cations with multiple oxidation states. Compared with undoped LaVO 3 and La 0.8 Sr 0.2 VO 4 nanofibers, perovskite La 0.8 Sr 0.2 VO 3 nanofibers exhibited an improved capacity of 2000 mA g −1 , and a 20‐times‐longer cycle life in LiO 2 batteries. X‐ray photoelectron spectroscopy, electron paramagnetic resonance spectroscopy, and photoluminescence analyses revealed that the performance variations mainly originated from crystal defects, which modulate oxygen reduction/evolution kinetics. Through in situ Raman analysis, we showed that these structural defects are closely related to the oxygen reduction/evolution behavior of La 0.8 Sr 0.2 VO 3 nanofibers and result in fewer parasitic reactions. This study offers insights into the potential rate capability of LiO 2 batteries and related devices.