Synthesis of TiO2/MOF-801(Zr) by a wet impregnation at room temperature for highly efficient photocatalytic reduction of Cr(Ⅵ)

Abstract

The research of metal organic frameworks materials of possessing semiconductor performance is important because they show great prospects on applications in wastewater treatment. In the current work, composites of TiO2/MOF-801(Zr) was prepared by a wet impregnation at room temperature, and a series of characterizations for catalysts, such as XRD, TEM, XPS, etc was investigated. The results of photocatalytic reduction of Cr(Ⅵ) under simulated solar light irradiation showed that 50%TiO2/MOF-801(Zr) exhibited better photocatalytic activity compared with other catalysts, which is attributed to synergistic effect including the interface enhancement effect and the enhancement of photogenerated carriers separation efficiency. The photocatalytic efficiency is as high as 98.1% when adjusting pH of reaction system to 1. It is most likely because the hydrogen cation concentration increased along with the increasing acidity, so that as to the promoting of reduction process of Cr(Ⅵ). In addition, we proposed a possible reaction mechanism of TiO2/MOF-801(Zr) composites for photocatalytic reduction of Cr(Ⅵ).