Sulfur-doped-titania coated on magnetite as magnetically recoverable photocatalyst for the UV-visible light-assisted-degradation of Congo red solution

Abstract

Novel magnetically recoverable photocatalysts of sulfur-doped-titania coated on magnetite, Fe3O4/TiO2-S, were synthesized through the sono-coprecipitation method involving Fe3O4, titanium tetraisopropoxide and thiourea as the sulfur source. The synthesized photocatalysts were then employed in the photodegradation of Congo red at pH 5 for 90 min. The results showed that Fe3O4/TiO2-S photocatalysts display very good photodegradation activity under UV light illumination. In addition, the sulfur doping strategy allows us to conduct the photodegradation of Congo red under visible light irradiation since it may reduce the photocatalyst bandgap energy and shift the wavelength to the visible light region. Moreover, the Fe3O4/TiO2-S 5% and 10% photocatalysts demonstrate excellent visible light-driven-photocatalytic degradation of Congo red with the photoactivity of 96.25% and 98.75%, respectively.