Preparation and Characterization of Thin Films TiO2 Prepared by Various Amount of Triton X-100 Surfactant for Photodegradation of a Dye Pollutant

Abstract

Dipping borosilicate glass in modified sol-gel solution was used to prepare thin film TiO2. The sol was prepared from titaniumtetraisopropoxide(TTIP), hydrochloric acid (conc. HCl), ethanol(EtOH), TritonX-100 surfactant and acetic acid(AcOH). The mole ratios of the starting solution were surfactant: EtOH: AcOH: TTIP: conc.HCl= R: 45: 6: 1: 0.1. The amounts of surfactant (R value) were varied as 0, 0.5, 1, 2, 3 and 4 moles, respectively. After dip-coated, the borosilicate glasses were dried at room temperature and heated for 15 minutes at 500 °C (rate3°C/min). The obtained films were uniform; however, varied in transparency, decreasing when the TritonX-100/TTIP mole ratios had been increased. The crystal structure, optical property and the morphology of thin films TiO2 were characterized by X-ray diffraction (XRD), UV–Vis spectroscopy, Environment Scanning Electron Microscope (E-SEM) and Atomic Force Microscopy (AFM). Spectra of XRD showed that all the TiO2 thin films were anatase phase. From UV–Vis technique, it was found that their UV absorption edges were approximately 380 nm. A cracking on the surface of TiO2 thin films appeared when the amounts of the surfactant were increased. From AFM image, TiO2 particles were spherical size, ranged from 11.2 to 35.5 nm and the roughness of the films increased with the increasing of TritonX-100/TTIP mole ratios. Under UV illumination, the photodegradation results of Reactive Yellow17 was pseudo the first order reaction and the film of TritonX-100/TTIP mole ratio = 1 : 1 was the highest removal efficiency with the apparent rate constant (k) = 2x10-2 min-1 and half life (t1/2) = 34.65 min.