Efficient adsorption and photocatalytic degradation of Rhodamine B dye over Bi2O3-bentonite nanocomposites: A kinetic study

Abstract Bi 2 O 3 -bentonite nanocomposites successfully synthesized by intercalation method, are used for photocatalytic degradation of Rhodamine B (Rh B) under visible light irradiation. Bi 2 O 3 -bentonite shows enhanced photocatalytic efficiency than pure Bi 2 O 3 due to intercalation with bentonite. Removal of Rh B is achieved upto 98.5% using 3 gL −1 photocatalyst at pH 3. It is found that increase in light absorption and decrease in electron-hole recombination enhances photocatalytic efficiency. Photocatalytic degradation of Rh B by Bi 2 O 3 -bentonite proceeds via advanced oxidative process. The plausible mechanism of photocatalytic degradation Rh B reported by LC-MS shows generation of different degradation products including benzoic acid and benzonium ion.