Preparation Of Modification TiO₂ Sensitized By Eosin Y And Performance Of Photocatalytic Hydrogen Evolution Under Visible Light Irradiation

In this thesis the preparation and modification of S(or Si)doped TiO₂ visible light photocatalyst sensitized by Eosin Y as well as its performance of photocatalytic hydrogen evolution was researched.The research works is composed of two parts:In the first part preparation of S-doped TiO₂ sensitized by Eosin Y and performance of photocatalytic hydrogen evolution under visible light irradiation was studied.S-doped TiO₂ calcined at different temperatures were prepared by sol-gel method.Pt was loaded on S-doped TiO₂ photocatalyst by photodeposition method. Eosin Y was absorbed on Pt-TiO₂ surface via impregnation method to prepare a series of dye-sensitization Eosin Y-Pt-S-TiO₂ visible light photocatalysts.The activity of the prepared photocatalyst under visible light irradiation was evaluated using photocatalytic hydrogen evolution as a probe reaction.It is found that the activity of Eosin Y-Pt-S-TiO₂ calcined at 600℃is the best.Samples were characterized by XRD, BET,FT-IR and UV-Vis DRS.It is found that the sensitization of Eosin Y extends the visible light response range of S-doped TiO₂.Eosin Y makes S-doped TiO₂ have a very strong absorption from 400 nm to 600 nm.With calcination temperature decreasing,the specific surface area of S-doped TiO₂ increases,and the hydroxyl amount on the surface of TiO₂ also increases,so that with the temperature decreasing, the adsorbed amount of Eosin Y also increases.Therefore the visible light photocatalytic activity of Eosin Y-Pt-S-TiO₂ enhances accordingly.In the sencond part preparation of Si-doped TiO₂ sensitized by Eosin Y and performance of photocatalytic hydrogen evolution under visible light irradiation was studied.Si-doped TiO₂ calcined at different temperatures were prepared by sol-gel method.Pt was loaded on the TiO₂,Si-TiO₂ photocatalysts by photodeposition method.Eosin Y was absorbed on Pt-TiO₂ and Pt-Si-TiO₂ surfaces via impregnation method to prepare two series of dye-sensitization photocatalysts Eosin Y- Pt-TiO₂ and Eosin Y-Pt-Si-TiO₂.The activity of the photocatalyst under visible light irradiation was evaluated using photocatalytic hydrogen evolution as a probe reaction.It is found that when the calcined temperature is 600℃,activities of both Eosin Y- Pt-TiO₂ and Eosin Y-Pt-Si-TiO₂ are the best and the activity of Eosin Y-Pt- Si -TiO₂ is about 3 times of Eosin Y-Pt-TiO₂.Samples were characterized by XRD,BET,FT-IR and UV-Vis DRS.It is found that the sensitization of Eosin Y extends the visible light response range of TiO₂ and Si -TiO₂.Eosin Y makes TiO₂,Si-TiO₂ have a very strong absorption from 400 nm to 600 nm.Doped Silicone can restrain the growth of crystal particle of TiO₂ and increase the specific surface area of TiO₂,so that the adsorbed amount of Eosin Y also increases.Therefore the visible light photocatalytic activity of Eosin Y-Pt-Si-TiO₂ enhances accordingly.