Fabrication of novel perovskite oxide Ba x Mn 1−x O 3 electrode for supercapacitors

Abstract

BaxMn1−xO3(x = 0.1, 0.15, 0.2) perovskite oxide is suitable material for fabrication of electrochemical devices due to its favorable chemical and physical properties. Ba-doped MnO3 (BaMnO3) has been synthesized by using hydrothermal process with varying concentration of Ba. Synthesized material was characterized by using X-ray diffraction (XRD), energy dispersive X-ray spectroscopy (EDX), scanning electron microscopy (SEM), and cyclic voltammetry (CV) to explore the physical and electrochemical properties. SEM results showed that synthesized materials exhibited nanorod-like morphology which was further controlled by doping. Furthermore, the surface area of the nanorods was increased on increasing dopant concentration which always boosts the electrochemical properties. The synthesized materials were highly pure and were confirmed by EDX. The structural properties were analyzed by XRD which confirmed the crystalline structure with crystallite size 22.1-11.3 nm where size of crystallites was decreased on increasing the dopant concentration. Furthermore, on increasing the doping, the oxygen vacancies were increased due to which the electrochemical properties were also enhanced. The electrochemical properties of the BaMnO3 perovskite oxide were characterized by CV and galvanostatic charge discharge (GCD) and showed the highest specific capacitance value of 433 F/g. The doped material also exhibited 104% high retention capacitance after 1000 cycles. Moreover, prepared BaMnO3 shows the good conductance behavior with 2.9 and 4 Ω values of effective series resistance and charge transfer resistance. Therefore, the effect of concentration of dopant and scan rate on specific capacitance was analyzed to optimize the best material for supercapacitor electrode.