Photocatalytic Reduction of 4-Nitrophenol over Bismuth Sulfur/Titanium Dioxide Heterojunction: Influence of Bismuth Sulfur Content on the Reaction Efficiency

Photocatalytic reduction of 4-nitrophenol is one of the most promising methods to remove this hazardous pollutant from wastewaters and generated a raw compound widely use in industrial processes. In the present work, three Bi2S3/TiO2 catalysts with different Bi2S3 content, were synthesized by a hydrothermal method. The materials were characterized by XRD, X-ray fluorescence, physisorption of N2, HRTEM, UV-Vis reflectance spectroscopy and zeta potential measurements. The catalytic activity of the synthesized materials was tested in the photoreduction of 4-nitrophenol in aqueous medium. Although the results indicate the formation of heterojunction for all the samples, the physicochemical properties of each material depend on the Bi2S3 content. The material with 6%wt of Bi2S3 exhibit the major catalytic activity, reducing 80% of the target molecule within 60 minutes of reaction.