Investigation of the Structure and Electrochemical Performance of Perovskite Oxide La1−xCaxCrO3 Utilized as Electrode Materials for Supercapacitors

Lanthanide perovskite materials are promising candidates for supercapacitor applications. In this study, a series of La1−xCaxCrO3 (x = 0–0.2) materials were prepared by sol-gel method, incorporating bivalent ions calcium at A-site. La0.85Ca0.15CrO3 exhibited the lowest charge transfer resistance and highest specific surface area. At 1 A/g, La0.85Ca0.15CrO3 achieved a maximum specific capacitance of 306 F/g, about 2.3 times higher than that of the LaCrO3 (133 F/g). Based on the observed data, a mechanism involving oxygen anion charge storage during the charging-discharging process is proposed. After 5000 long cycle, the coulomb efficiency of the electrode remains above 94%. These results demonstrate that Ca-substituted compounds exhibit significant potential for A-site engineering in supercapacitor applications.