Boron-doped cobalt oxide thin films and its electrochemical properties

The cobalt oxide and boron-doped cobalt oxide thin films were produced by spray deposition method. All films were obtained onto glass and fluorine-doped tin oxide (FTO) substrates at 400 degrees C and annealed at 550 degrees C. We present detailed analysis of the morphological and optical properties of films. XRD results show that boron doping disrupts the structure of the films. Morphologies of the films were investigated by using a scanning electron microscopy (SEM). Optical measurements indicate that the band gap energies of the films change with boron concentrations. The electrochemical supercapacitor performance test has been studied in aqueous 6 M KOH electrolyte and with scan rate of 5 mV/s. Measurements show that the largest capacitance is obtained for 3% boron-doped cobalt oxide film.