Bismuth Titanate films produced by the tanodic spark deposition technique

Polycrystalline bismuth titanate (Bi12TiO20) films were prepared on bismuth substrates with an electrochemical process based on the anodic spark deposition in an aqueous electrolyte at room temperature. The X-ray diffraction (XRD) and field emission scanning electron microscopy (FE-SEM) results revealed that varying current density (CD) can tailor the microstructure and optical property of Bi12TiO20 films. The higher the electric current, the more favored the crystallinity of Bi12TiO20 phase. At lower CD of 0.25 A cm−2 the films with uniformly distributed small grains of ca. 25 nm were prepared, while the films formed at higher CD of 0.75 A cm−2 were composed of large grains accompanied by many crater-like pores. UV-vis adsorption spectra showed that all the prepared Bi12TiO20 films exhibited good absorption ability both in UV and visible light regions.