A TiO2 photocatalyst is coated on the surface of a zeolite fly ash bead(ZFAB) to improve its dispersability and exposure degree in a cement system.The application of Ag particles in TiO2/ZFAB modified cementitious m...A TiO2 photocatalyst is coated on the surface of a zeolite fly ash bead(ZFAB) to improve its dispersability and exposure degree in a cement system.The application of Ag particles in TiO2/ZFAB modified cementitious materials is to further enhance the photocatalytic performance.Various Ag@TiO2/ZFAB modified cementitious specimens with different Ag dosages are prepared and the characteristics and photocatalytic performance of the prepared samples are investigated.It is observed that the multi-level pore structure of ZFAB can improve the exposure degree of TiO2 in a cement system and is also useful to enhance the photocatalytic efficiency.With an increment of the amounts of Ag particles in the TiO2/ZFAB modified cementitious samples,the photocatalytic activities increased first and then decreased.The optimal Ag@TiO2/ZFAB modified cementitious sample reveals the maximum reaction rate constant for degrading benzene(9.91×10^-3 min^-1),which is approximately 3 and 10 times higher than those of TiO2/ZFAB and TiO2 modified samples,respectively.This suggests that suitable Ag particles coupled with a ZFAB carrier could effectively enhance the photocatalytic effects and use of TiO2 in a cement system.Thus,ZFAB as a carrier could provide a potential method for a high efficiency engineering application of TiO2 in the construction field.展开更多
Photocatalyst CoPcS/TiO2 was prepared by sol-gel method. Composite CoPcS/TiO2/K2Ti4O9 was prepared by dipping. It was incandesced at various temperatures and modification effect was compared. The results showed that o...Photocatalyst CoPcS/TiO2 was prepared by sol-gel method. Composite CoPcS/TiO2/K2Ti4O9 was prepared by dipping. It was incandesced at various temperatures and modification effect was compared. The results showed that optical absorption of sample incandesce at 423K occurred significant red-shift. Light absorption width extended from ultraviolet region to visible region, especially there was an intensive absorption between 600 nm and 680 nm. X-ray diffraction spectrogram showed that TiO2 in sample still maintained anatase crystal form. Under the illumination of visible light, photocatalysis degradation experiment was taken with Eosin B as simulated pollutants. Decoloration rate of Eosin B was much improved. The rate can reach 80% in 300 minutes.展开更多
基金supported by the National Natural Science Foundation of China (51478370)the Engineering and Physical Sciences Research Council of UK–Natural Science Foundation of China (EPSRC-NSFC) International Joint Research Project (51461135005)~~
文摘A TiO2 photocatalyst is coated on the surface of a zeolite fly ash bead(ZFAB) to improve its dispersability and exposure degree in a cement system.The application of Ag particles in TiO2/ZFAB modified cementitious materials is to further enhance the photocatalytic performance.Various Ag@TiO2/ZFAB modified cementitious specimens with different Ag dosages are prepared and the characteristics and photocatalytic performance of the prepared samples are investigated.It is observed that the multi-level pore structure of ZFAB can improve the exposure degree of TiO2 in a cement system and is also useful to enhance the photocatalytic efficiency.With an increment of the amounts of Ag particles in the TiO2/ZFAB modified cementitious samples,the photocatalytic activities increased first and then decreased.The optimal Ag@TiO2/ZFAB modified cementitious sample reveals the maximum reaction rate constant for degrading benzene(9.91×10^-3 min^-1),which is approximately 3 and 10 times higher than those of TiO2/ZFAB and TiO2 modified samples,respectively.This suggests that suitable Ag particles coupled with a ZFAB carrier could effectively enhance the photocatalytic effects and use of TiO2 in a cement system.Thus,ZFAB as a carrier could provide a potential method for a high efficiency engineering application of TiO2 in the construction field.
基金Acknowledgements: This project is supported by the fund of the Plan of Postgraduate Scientific Research Innovation of Jiangsu Province (No. CX07B_175z) and the Natural Science Foundation of Henan Province (No. 0624720029).
文摘Photocatalyst CoPcS/TiO2 was prepared by sol-gel method. Composite CoPcS/TiO2/K2Ti4O9 was prepared by dipping. It was incandesced at various temperatures and modification effect was compared. The results showed that optical absorption of sample incandesce at 423K occurred significant red-shift. Light absorption width extended from ultraviolet region to visible region, especially there was an intensive absorption between 600 nm and 680 nm. X-ray diffraction spectrogram showed that TiO2 in sample still maintained anatase crystal form. Under the illumination of visible light, photocatalysis degradation experiment was taken with Eosin B as simulated pollutants. Decoloration rate of Eosin B was much improved. The rate can reach 80% in 300 minutes.