Honeycomb LaMnO₃ Perovskite Synthesized by a Carbon Sphere as a Self-Sacrificing Template for Supercapacitors

Abstract

A honeycomb-shaped LaMnO3 supercapacitor material has been successfully fabricated by a sol–gel method utilizing an as-prepared carbon sphere material as a template to control the morphology. The as-prepared materials were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and the N2 adsorption–desorption isotherm method. Electrochemical tests including cyclic voltammetry (CV), galvanostatic charge and discharge (GCD) measurements, electrochemical impedance spectroscopy (EIS), and cycle life were also carried out to investigate the supercapacitor performance of the as-prepared materials. The experimental results reveal that when the calcination temperature of the dry gel is 600 °C, the performance of the honeycomb LaMnO3 perovskites is better, and the specific capacitance (535 F g–1) of the honeycomb LaMnO3 perovskites is higher than that of LaMnO3 perovskites prepared by the sol–gel method without adding the carbon sphere as the template (247 F g–1). Therefore, as far as supercapacitor materials are concerned, the preparation method of honeycomb LaMnO3 perovskites displays better application prospects.