Preparation And Application Of Ag/S Doped Black Titanium Dioxide Nanorods

In recent years,semiconductor photocatalysts have attracted a great deal of attention due to their potential applications in environmental remediation and solar energy conversion.As the most promising semiconductor photocatalyst,TiO₂ has been extensively investigated in environmental cleaning and green energy production,due to its safety,low-cost,high chemical stability,and good photoelectric performance under ultraviolet light irradiation.However,as a representative broad band gap energy semiconductor（3.2 eV for anatase and 3.0 eV for rutile）,TiO₂ mainly responses to ultraviolet light.And it has a lower charge transfer rate and a high recombination rate of electron-hole pairs,which greatly limits the efficiency of solar energy conversion.In order to improve the photocatalytic activity of titanium dioxide in visible region,it can be modified by element doping,Ti³⁺self-doping,morphology construction and noble metal deposition.In this paper,one dimensional rod-shaped black S-TiO₂ and Ag loaded black S-TiO₂photocatalytic materials are prepared with different synthetic routes.The prepared photocatalysts are characterized by XRD,Raman,SEM,TEM,XPS,UV-Vis,and FT-IR.In addition,photocatalytic degradation of methyl orange and phenol,photocatalytic hydrogen production and photoelectric properties are tested.The results are analyzed,and the reusability and mechanism of the prepared materials are studied and discussed.The results show that the prepared b-700-TR is successfully doped with S and Ti³⁺possessing one-dimensional nanorods structure.Due to co-doping of S and Ti³⁺,the band gap is greatly reduced to 2.56 e V,and the optical absorption range of the catalyst is successfully extended to the visible light region.Moreover,the degradation rates of methyl orange and phenol reach 91.48%and 92.54%,respectively.At the same time,photocatalytic hydrogen evolution rate is 166μmol·h^-1·g^-1.In the cycle test,the activity of the sample is almost no decrease,indicating the good cyclic stability.Besides,the Ag/S-TiO2-x is prepared by photo-deposition method showing better photocatalytic activity due to the surface plasmon resonance effect of Ag.Meanwhile,the photocatalytic degradation efficiency of methyl orange and phenol are as high as98.12%and 98.67%,respectively.And the hydrogen production rate is 209.2μmol·h^-1·g^-1.Similarly,In the cycle test,the activity of the sample is almost no decrease,indicating the good cyclic stability.