TiO2/T-PVA Composites Immobilized on Cordierite: Structure and Photocatalytic Activity for Degrading RhB Under Visible Light

A novel immobilized visible light-active photocatalyst (TiO2/polyvinyl alcohol after thermal treatment (T-PVA)/cordierite honeycomb (CHC)) was successfully prepared by a simple and convenient method combining sol-gel and thermal treatment using tetrabutyl titanate (TBOT) as the titanium source, polyvinyl alcohol (PVA) as the precursor of conjugated polymer, and CHC as the support. The synthesized photocatalyst was characterized by X-ray diffraction, Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, ultraviolet-visible diffuse reflectance spectroscopy, and field emission scanning electron microscopy. The results showed that PVA was dehydrated to produce conjugated unsaturated T-PVA. The T-PVA not only extended the response spectrum of TiO2 to visible light region, but also strengthened the adhesion of TiO2 to CHC. The TiO2/T-PVA/CHC showed both outstanding adsorption properties and excellent photocatalytic performance under visible light on the decolorization of Rhodamine B. Over eight cycles, the photocatalyst continued to maintain perfect photocatalytic activity, showing good stability.