TiO2 films have received increasing attention for the removal of organic pollutants via photocatalysis. To develop a simple and effective method for improving the photodegradation efficiency of pollutants in surface w...TiO2 films have received increasing attention for the removal of organic pollutants via photocatalysis. To develop a simple and effective method for improving the photodegradation efficiency of pollutants in surface water, we herein examined the preparation of a P25-TiO2 composite film on a cement substrate via a sol–gel method. In this case, Rhodamine B（Rh B）was employed as the target organic pollutant. The self-generated TiO2 film and the P25-TiO2 composite film were characterized by X-ray diffraction（XRD）, N2 adsorption/desorption measurements, scanning electron microscopy（SEM）, transmission electron microscopy（TEM）, and diffuse reflectance spectroscopy（DRS）. The photodegradation efficiencies of the two films were studied by Rh B removal in water under UV（ultraviolet） irradiation. Over 4 day exposure, the P25-TiO2 composite film exhibited higher photocatalytic performance than the self-generated TiO2 film. The photodegradation rate indicated that the efficiency of the P25-TiO2 composite film was enhanced by the addition of the rutile phase Degussa P25 powder. As such, cooperation between the anatase TiO2 and rutile P25 nanoparticles was beneficial for separation of the photo-induced electrons and holes. In addition, the influence of P25 doping on the P25-TiO2 composite films was evaluated. We found that up to a certain saturation point, increased doping enhanced the photodegradation ability of the composite film. Thus, we herein demonstrated that the doping of P25 powders is a simple but effective strategy to prepare a P25-TiO2 composite film on a cement substrate, and the resulting film exhibits excellent removal efficiency in the degradation of organic pollutants.展开更多
The influence of NH3-treating temperature on the visible light photocatalytic activity of N-doped P25-TiO2 as well as the relationship between the surface composition structure of TiO2 and its visible light photocatal...The influence of NH3-treating temperature on the visible light photocatalytic activity of N-doped P25-TiO2 as well as the relationship between the surface composition structure of TiO2 and its visible light photocatalytic activity were investigated.The results showed that N-doped P25-TiO2 treated at 600℃ had the highest activity.The structure of P25-TiO2 was converted from anatase to rutile at 700℃.Moreover,no N-doping was detected at the surface of P25-TiO2.There was no simply linear relationship between the visible light photocatalytic activity and the concentration of doped nitrogen,and visible light absorption.The visible light photocatalytic activity of N-doped P25-TiO2 was mainly influenced by the synergistic action of the following factors:(i) the formation of the single-electron-trapped oxygen vacancies(denoted as Vo);(ii) the doped nitrogen on the surface of TiO2;(iii) the anatase TiO2 structure.展开更多
In(OH)3 photocatalyst was prepared using ultrasonic hydrolysis precipitation followed by calcining at temperature lower than 160 ℃.The characterizations by XRD,DRS,TG-DSC,TEM and FTIR show that the solid is a cubic c...In(OH)3 photocatalyst was prepared using ultrasonic hydrolysis precipitation followed by calcining at temperature lower than 160 ℃.The characterizations by XRD,DRS,TG-DSC,TEM and FTIR show that the solid is a cubic crystal with 10—15 nm size,and has two band gaps,direct band gap 5.48 and indirect gap 5.02 eV.Evaluation of the photocatalytic activity toward oxidation reactions of benzene under UV irradiation(λmax=254 nm) showed that In(OH)3 presented much higher photoactivity and active stability than commercial Degussa-P25 TiO2.FTIR characterization for the samples before and after the photocatalytic reaction suggested that the better photocatalytic behavior of In(OH)3 than the TiO2 is due to lower aggradations of the intermediate species on its surface in photocatalytic process.展开更多
基金supported by the National Science Funds for Creative Research Groups of China (No. 51421006)the National Major Projects of Water Pollution Control and Management Technology (No. 2017ZX07204003)+2 种基金the National Key Plan for Research and Development of China (2016YFC0502203)the Key Program of National Natural Science Foundation of China (No. 91647206)the Qing Lan Project of Jiangsu Province, and PAPD
文摘TiO2 films have received increasing attention for the removal of organic pollutants via photocatalysis. To develop a simple and effective method for improving the photodegradation efficiency of pollutants in surface water, we herein examined the preparation of a P25-TiO2 composite film on a cement substrate via a sol–gel method. In this case, Rhodamine B（Rh B）was employed as the target organic pollutant. The self-generated TiO2 film and the P25-TiO2 composite film were characterized by X-ray diffraction（XRD）, N2 adsorption/desorption measurements, scanning electron microscopy（SEM）, transmission electron microscopy（TEM）, and diffuse reflectance spectroscopy（DRS）. The photodegradation efficiencies of the two films were studied by Rh B removal in water under UV（ultraviolet） irradiation. Over 4 day exposure, the P25-TiO2 composite film exhibited higher photocatalytic performance than the self-generated TiO2 film. The photodegradation rate indicated that the efficiency of the P25-TiO2 composite film was enhanced by the addition of the rutile phase Degussa P25 powder. As such, cooperation between the anatase TiO2 and rutile P25 nanoparticles was beneficial for separation of the photo-induced electrons and holes. In addition, the influence of P25 doping on the P25-TiO2 composite films was evaluated. We found that up to a certain saturation point, increased doping enhanced the photodegradation ability of the composite film. Thus, we herein demonstrated that the doping of P25 powders is a simple but effective strategy to prepare a P25-TiO2 composite film on a cement substrate, and the resulting film exhibits excellent removal efficiency in the degradation of organic pollutants.
文摘The influence of NH3-treating temperature on the visible light photocatalytic activity of N-doped P25-TiO2 as well as the relationship between the surface composition structure of TiO2 and its visible light photocatalytic activity were investigated.The results showed that N-doped P25-TiO2 treated at 600℃ had the highest activity.The structure of P25-TiO2 was converted from anatase to rutile at 700℃.Moreover,no N-doping was detected at the surface of P25-TiO2.There was no simply linear relationship between the visible light photocatalytic activity and the concentration of doped nitrogen,and visible light absorption.The visible light photocatalytic activity of N-doped P25-TiO2 was mainly influenced by the synergistic action of the following factors:(i) the formation of the single-electron-trapped oxygen vacancies(denoted as Vo);(ii) the doped nitrogen on the surface of TiO2;(iii) the anatase TiO2 structure.
文摘In(OH)3 photocatalyst was prepared using ultrasonic hydrolysis precipitation followed by calcining at temperature lower than 160 ℃.The characterizations by XRD,DRS,TG-DSC,TEM and FTIR show that the solid is a cubic crystal with 10—15 nm size,and has two band gaps,direct band gap 5.48 and indirect gap 5.02 eV.Evaluation of the photocatalytic activity toward oxidation reactions of benzene under UV irradiation(λmax=254 nm) showed that In(OH)3 presented much higher photoactivity and active stability than commercial Degussa-P25 TiO2.FTIR characterization for the samples before and after the photocatalytic reaction suggested that the better photocatalytic behavior of In(OH)3 than the TiO2 is due to lower aggradations of the intermediate species on its surface in photocatalytic process.
