This work describes the preparation of an Al2O3 electrode material for a performing and stable supercapacitor. The electrode was prepared by a DC thermal plasma plant installed at ENEA Research Centre of Portici. The structures and morphologies of samples were characterized by SEM, XRD, TG, and FT-IR. Al2O3 electrode electrochemical characteristics were performed in a sulphuric acid solution electrolyte. Cyclic Voltammetry (CV) technique was carried out. The results show that Al2O3 exhibits a good specific capacitance. Furthermore, after 10000 cycles, 98% of the initial capacitance was maintained.