Preparation, Characterization and Photoelectrochemical Investigation of p-Type Nanostructured Cobalt Titanate

Nanostructured CoTiO₃ was prepared by a low temperature modified sol-gel method using tetraisopropylorthotitanate as the sourse of Ti, cobalt nitrate as the source of cobalt, ethylene glycol and ethanol and a calcination temperature of 550°C. X-ray differactometry and transmission electron microscopy were used for characterization of crystal structure and morphology of prepared materials. A crystallite size of 57 nm for cobalt titanate and a nanoparticle size smaller than 70 nm were obtained for prepared samples. The band gap of prepared nanostructured cobalt titanate was determined optically by UV-Vis diffuse reflectance spectroscopy. Using electrochemical impedance spectroscopy and Mott-Schottky analysis, the energy band structures of nanostructured CoTiO₃ were determined and its cyclic voltammograms were interpreted in terms of its energy band structure.