Paper-TiO2 composite: An effective photocatalyst for 2-propanol degradation in gas phase

Two simple routes for the synthesis of a paper-TiO2 composite were tuned up and the efficiency of the resulting paper-TiO2 photocatalyst was investigated in the 2-propanol oxidation in gas phase. The first route involved the in-situ generation over the sheet of paper of a TiO2 layer starting from a solution of Ti (OBu)4 in tert-butanoliacetic acid, followed by hydrothermal treatment at 120 degrees C for 3 h. The sample was labelled as paper-TiO2 (H). The second approach was based on the adsorption on the paper of a ready-made suspension of titania nanoparticles (TiO2 sol), generated in autoclave at 140 degrees C and stable in acid medium at pH <3. The sample was labelled as paper-TiO2 (S). Evidence of the generation of crystalline TiO2 was confirmed by Raman spectroscopy and the morphology of the TiO2 layer was analyzed by FE-SEM microscopy. The optical properties of the two paper-TiO2 samples and the surface and bulk chemical compositions were studied by UV-vis, XPS spectroscopies and TGA analysis as well. The surface properties of the two paper-TiO2 composites in term of wettability were also investigated through water contact angle measurements. The photocatalytic oxidation of 2-propanol in gas phase, under simulated sunlight irradiation in presence of the two paper-TiO2 samples was studied at room temperature and compared with a commercial sample, TiO2 P25 (Evonik). Both functionalization approaches led to a photoactive paper capable of the complete decomposition of 2-propanol in CO2 and H2O within acceptable timescale. The photocatalytic performances of both paper-TiO2 composites compare favorably with TiO2 P25. (C) 2017 Elsevier B.V. All rights reserved.