Superiority of Cubic Perovskites Oxides with Strong B-O Hybridization for Oxygen-Anion Intercalation Pseudocapacitance

Perovskite materials can store charge through rapid oxygen anions intercalation. Although numerous perovskite materials owing to rich selections of A and B-site elements are reported as electrodes of supercapatteries, the effect of the crystal structure of perovskite materials on their electrochemical performance has never been studied so far. Herein, using SrCo 0.9 Mo 0.1 O 3− δ , SrFeO 3− δ , Ba 0.5 Sr 0.5 Co 0.8 Fe 0.2 O 3− δ , and LaMnO 3− δ as research targets, it is proved that their corresponding cubic structure materials display the best electrochemical performance. And then, the origin of such superiority of cubic structure for SrCo 0.9 Mo 0.1 O 3− δ is explored through experimental investigations and theoretical calculations. The results show that the increase in the content of oxygen vacancies and the enhancement of B-O hybridization of cubic structure can optimize the electronic structure of the perovskite materials, thereby improving its conductivity and accelerating the reaction kinetics. The filtering strategy based on crystal structure proposed by this report will provide a new perspective to faster and more efficient choice of perovskite materials for supercapatteries.