Bita Sadeghi - Department of Chemistry, AmirKabir University of Technology (Polytechnic), Tehran, Iran
Mitra Najafloo - Department of Chemistry, AmirKabir University of Technology (Polytechnic), Tehran, Iran
Leila Naji - Department of Chemistry, AmirKabir University of Technology (Polytechnic), Tehran, Iran

In this study, the sol-gel method was employed to synthesize perovskite LaNiO۳, a novel pseudocapacitive electrode with anion intercalation. The electrode's performance was thoroughly investigated by analyzing its CV, EIS, and GCD curves in a KOH electrolyte. In addition, the XRD, SEM, and EDX techniques were employed to analyze the phase composition, microstructure, and surface chemistry of the LaNiO۳ powders. According to the data, the exceptional pseudocapacities of LaNiO۳ are demonstrated by its specific capacitance of ۱۶۵۷ F g-۱ at ۱ A/g. The storage of charge in this perovskite pseudocapacitor electrode is connected to the insertion of oxygen ions into oxygen vacancies. This process is mainly caused by the changes in the valence states of the B site nickel in the perovskite ABO۳ structure. The mechanism of oxygen intercalation and extrusion in the LaNiO۳ electrode is also elucidated.

Perovskite LaNiO۳; Pseudocapacitor; Anion-based intercalation; Oxygen vacancy