Structural, optical and photocatalytic properties of BiFeO3 nanoparticles

Abstract

BiFeO3 (BFO) 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. BFO is p-type semiconductor where determined band gap was 2.20 eV, indicating its potential application as visible-light-response photocatalyst. Mott-Schottky measurements were performed to determine flat band potential and position of valence and conduction bands. Obtained BFO 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. Photodegradation products were analyzied by HPLC technique, and mechanism of photocatalytic degradation of organic dye was proposed.