Photodegradation of organic dye using BiFeO3 particles synthesized by ultrasound route

Abstract

BiFeO3 precursor powder was synthesized by ultrasound asissted sol–gel route at relatively low temperature, starting from Bi-nitrate, Fe-nitrate, and ethylene glycol. Structural, optical, and photocatalytic properties of the obtained powder were investigated. X-ray diffraction analysis confirmed that thermal treatment of precursor powder at 500 °C led to formation of pure phase BiFeO3. The determined band gap was 2.20 eV, indicating its potential application as visible-light-response photocatalyst. The powder is used for photocatalytic degradation of typical organic azo dye Mordant Blue 9 in concentration of 50 mg/l. Measurements were performed for different times of irradiation and pH of the dye solution. Changes in UV-Vis absorption spectra revealed the decolorization and decomposition of organic dye during the photodegradation process. Photodegradation products were analyzied by HPLC technique, and mechanism of photocatalytic degradation of organic dye was proposed.