Effect of Pd doping on the structural properties and supercapacitor performance of La_0.8Sr_0.2Cu_0.7Mn_0.3O_{3< /sub> and La0.8Sr0.2Cu0.4Mn0.6O3< /sub> as electrode materials}

La0.8Sr0.2Cu0.4Mn0.6O3 (LSCM0.6) and La0.8Sr0.2Cu0.7Mn0.3O3 (LSCM0.3) were prepared and Pd (10 % mole in B site) was partial substituted in the B site, with the aim of investigating their performance as supercapacitor electrodes. The crystal structure, morphology and electrochemical activity of them studied in details. LSCM0.3 has a cubic structure and belongs to the Pm-3 m space group. The partial substitution of Pd in B site, increased the distortion of the structure and oxygen vacancies. La0.8Sr0.2(Cu0.4Mn0.6)(0.9)Pd0.1O3 (LSCMP0.6) recognized to be the best sample of the synthesized. This sample showed obvious pseudo-capacitive behavior and the highest specific capacitance (113 F.g(-1)) at a current density of 1 A.g(-1). The improved electrochemical activity of LSCMP0.6 were originated from the structural features and higher oxygen vacancy content. Extensive charge-discharge cycles performed to assess the electrochemical stability of LSCMP0.6. It was found, after 3000 charge-discharge cycles, the specific capacitance dropped to about 70 % of its initial value.