Enhanced photocatalytic activity of titanium dioxide by β-cyclodextrin in decoloration of Acid Yellow 99 dye

摘要

Photocatalytic decoloration of Acid Yellow 99 dye by TiO_2 has been investigated under different experimental conditions. Addition of β-Cyclodextrin on TiO_2 enhanced the photoac-tivity of TiO_2 in AY99 degradation. Optimal experimental conditions on catalyst amount, pH value, illumination time, and dye concentration have been determined. The mineralization of AY99 has been confirmed by Chemical Oxygen Demand measurements. The higher photoac-tivity of TiO_2-β-CD/visible light system than TiO_2/visible light system can be ascribed due to the ligand to metal charge transfer from β-CD to Ti~Ⅳ located in an octahedral coordination environment. The complexation patterns have been confirmed with UV-Visible and FT-IR spectral data. The interactions between TiO_2 and β-CD have been characterized by Field Emission Scanning Electron Microscopy, X-ray powder diffraction analysis, and UV-Visible diffuse reflectance spectroscopy.