《Study of the Bandgap of Synthesized Titanium Dioxide Nanoparticules》.pdfVIP

The Open Materials Science Journal, 2010, 4, 9-14 9 Open Access Study of the Bandgap of Synthesized Titanium Dioxide Nanoparticules Using the Sol-Gel Method and a Hydrothermal Treatment * Sergio Valencia, Juan Miguel Marín and Gloria Restrepo Applied Physical Chemistry Processes, University of Antioquia, Medellin, Colombia Abstract: In this work optical properties of titanium dioxide nanoparticles were studied. Titanium dioxide nanoparticles were synthesized by the sol-gel method followed by a hydrothermal treatment using tetraisopropyl orthotitanate (TIOT) and 2-propanol. The synthesized samples were characterized by X-ray diffraction (XRD), UV-Vis diffuse reflectance spectroscopy (UV/DRS) and nitrogen adsorption-desorption methods. The bandgap energy was obtained using the Kubelka-Munk reemission function. The catalyst synthesized with a molar ratio of R1 (water/TIOT) = 3.5 and R2 (2-propanol/TIOT) = 15 has a predominately anatase phase. It also has a high photo degradation of methyl orange compared to TiO2 Degussa P-25. A shift band gap energy of 3.27 was observed. Keywords: Titanium dioxide, hydrothermal treatment, sol-gel method, band gap. 1. INTRODUCTION method and the hydrothermal treatment, using a crystallization temperature of 200ºC for 2