Bismuth tungstate incorporated zirconium metal–organic framework composite with enhanced visible-light photocatalytic performance

Abstract

Metal–organic frameworks (MOFs) have many outstanding properties that make them candidate materials for the development of high performance catalysts. Visible-light promoted photocatalysis for the degradation of organic pollutants is a promising direction in the field of water treatment. However, studies applying MOFs as photocatalyst for water treatment are very limited. In this study, UiO-66, a zirconium based MOF, was incorporated with bismuth tungstate (Bi₂WO₆) by a simple hydrothermal method for the development of visible-light photocatalysts. The Bi₂WO₆/UiO-66 composite not only exhibited enhanced photocatalytic activity for the degradation of Rhodamine B (RhB) under visible-light irradiation, but also showed good catalyst stability. In the recycled dye degradation experiments, most activity of the composite was reserved, and the structure and morphology of the composite did not vary after the experiment of dye degradation, either. The photocatalytic activity of Bi₂WO₆/UiO-66 composites with varying Bi : Zr molar ratios were investigated and the optimum Bi₂WO₆ content was found. Also, by introducing different scavengers to compete for the active species involved in the degradation process, the mechanism of the photocatalytic degradation of RhB by the Bi₂WO₆/UiO-66 composite was studied.