Characterization of Sb doped SnO2 films prepared by spray technique and their application to photocurrent generation

Pure and antimony doped tin oxide films (SnO2:Sb) have been prepared by a chemical spray technique on silica glass substrates. X-ray diffraction (XRD), atomic force microscopy (AFM), UV-Vis spectroscopy, Fourier transform infrared spectroscopy (FTIR), electrochemical impedances spectroscopy (EIS) and electrochemical photocurrent (ECP) measurements were used to characterize the obtained films. The results of XRD indicated that all films exhibited tetragonal cassiterite SnO2 structure. The Sb-doped films showed a transparency more than 70% in the visible region and the Sb inclusion in the cassiterite lattice reduced the transparency in this region. EIS spectra have a single semi-circle in the high frequency region and the diameter of half-circle was found to decrease in the presence of small amount of Sb doping (2%). Electrochemical photocurrent test showed that the maximum increasing current under ultraviolet light was obtained for a doping level of 4%.