F/W co-doped TiO2-SiO2 composite aerogels with improved visible light-driven photocatalytic activity

摘要

In order to further improve the photocatalytic activity of TiO2-SiO2 composite aerogels under the irradiation of visible light, F/W coped TiO2-SiO2 (F-y-W0.02TiO2-SiO2) composite aerogel was prepared by ambient pressure drying with solvothermal assisted crystallization process. The microstructure and photocatalytic activity of the composite aerogels under visible light irradiation were investigated. The results indicate that the obtained F-y-W0.02TiO2-SiO2 composite aerogels exhibited typical mesoporous structure with higher specific surface area 105-223 m(2)/g and pore volume 0.51-0.66 cc/g. Adding appropriate amount of HF into the composite sol is favorable for enlarging the pore volume and pore size of the aerogel products, and the F-y-W0.02TiO2-SiO2 composite aerogels with F/W molar ratio = 0.1 exhibited the highest removing efficiency for the pollutant rhodamine B in the water. In addition, the quantum efficiency of the samples was investigated by assembling a dye-sensitized solar cells (DSSC) using the F-y-W0.02TiO2-SiO2 composite aerogel coating as the photoanode, and it was found that the F-y-W0.02TiO2-SiO2 composite aerogel with F/W molar ratio = 0.1 exhibited higher photoelectron conversion efficiency.