TiO2 immobilized on SiO2 (TiO2 /SiO2 ) have been prepared by sol-gel method and various ions of transition metals (Cr3+ , Co2+ , Ni2+ , Cu2+ , and Zn2+ )weredoped on the photocatalyst usingwet impregnation me...TiO2 immobilized on SiO2 (TiO2 /SiO2 ) have been prepared by sol-gel method and various ions of transition metals (Cr3+ , Co2+ , Ni2+ , Cu2+ , and Zn2+ )weredoped on the photocatalyst usingwet impregnation method under reducing calcination atmosphere. The photocatalytic activity of metaldoped TiO2 /SiO2 towards phenoldegradation under black light irradiationwere investigated and comparedwith undoped TiO2 /SiO2 . The results showed that the photoresponse of Cu2+ and Zn2+doped TiO2 /SiO2were larger than undoped TiO2 /SiO2 , indicating that the photogenerated carrierswere separated more efficiently in Cu2+ and Zn2+doped TiO2 /SiO2 . The reactivitywas in the order of Cu2+ 〉 Zn2+ 〉 Ni2+ 〉 Cr3+ 〉 Co2+ . Thedifferent photoreactivitywas ascribed to combine effect of thedifferent ionic radii and photocorrison tendency of thedopants. The samplewas also characterized by surface analytical methods such as X-raydiffraction, scanning electron micrograph/electrondispersive X-ray analyzer and UV-Vis absorption spectrum.展开更多
The paper introduces the preparation of floating TiO2/beads photocalyst attached to the hollow glass micro-beads surface by sol-gel technique using tetrabutyl titanate as material and the preparation of floating CoPcS...The paper introduces the preparation of floating TiO2/beads photocalyst attached to the hollow glass micro-beads surface by sol-gel technique using tetrabutyl titanate as material and the preparation of floating CoPcS/TiO2/beads by dip-coatig technique. The optimal factor of degradation of vegetable oil floating on water using CoPcS/TiO2/beads was studied. The result showed that the removal rate of vegetable oil floating on water can highly reach 90% at the optimal condition (acidity or neutrality, 375W medium-pressure mercury vapour lamp, illumination 2h-3h, lg CoPcS/TiO2/beads). The photocatalytic removal efficiency causing by CoPcS/TiO2/beads was increased rapidly by adding a trace amount of H2O2.展开更多
Cerium-doped SiO2/TiO2 nanostructured fibers were fabricated by electrospinning technology. The prepared fibers were characterized by thermogravimetric analysis (TGA), scanning electron microscopy (SEM), X-ray dif...Cerium-doped SiO2/TiO2 nanostructured fibers were fabricated by electrospinning technology. The prepared fibers were characterized by thermogravimetric analysis (TGA), scanning electron microscopy (SEM), X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FT-IR). Using the fibers as catalysts, photoeatalytic degradation of Methylene Blue (MB) aqueous solution was carded out under simulated sunlight. The 0.2% Ce doping proved to be the optimal concentration for the doping of TiO2/SiO2, compared to other Ce-doped molar concentrations. The 0.2% Ce-doped SiOdTiO2 fibers exhibited higher photocatalytic activity than industrial Degussa P25 and the samples doped with only Ce or SIO2. The reasons for improving the photocatalytic activity were also discussed. Several operational parameters were studied, which showed that the photocatalytic efficiency of MB was influenced by parameters such as the initial dye concentration, the initial pH, inorganic anions, and so on. In addition, the influences of an electron acceptor and a radical scavenger suggested that OH was the dominant photooxidant during the photocatalytic process. The reuse evaluation of the fibers indicated that their photocatalytic activity had good stability.展开更多
TiO2/SiO2 aerogels with different molar ratio of SiO2/TiO2 were prepared via non-supercritical method using tetrabutyl titanate and silica sols as raw materials. The samples were characterized by TEM, SEM, BET, IR, XR...TiO2/SiO2 aerogels with different molar ratio of SiO2/TiO2 were prepared via non-supercritical method using tetrabutyl titanate and silica sols as raw materials. The samples were characterized by TEM, SEM, BET, IR, XRD and so on. The results indicate that the BET surface area of TiO2/SiO2 aerogels calcined at 550℃ which consisted of anatase structure of TiO2 with narrow distribution pores of 5-25 nm is as high as 357.89 m2·g-1. For the photocatalytic degradation of pyridine, the catalytic activities of TiO2/SiO2 aerogels are much higher than that of TiO2 powder. The photocatalytic activity of TiO2/SiO2 aerogels calcined at 800℃ is the optimum. The higher the content of SiO2, the higher the photocatalytic activity of TiO2/SiO2 aerogels. The cost for preparation of the aerogels is greatly reduced by using non-supercritical drying method, and the aerogels are hopefully applied in the treatment of industrial waste water such as coking effluent treatment.展开更多
摘要TiO2 immobilized on SiO2 (TiO2 /SiO2 ) have been prepared by sol-gel method and various ions of transition metals (Cr3+ , Co2+ , Ni2+ , Cu2+ , and Zn2+ )weredoped on the photocatalyst usingwet impregnation method under reducing calcination atmosphere. The photocatalytic activity of metaldoped TiO2 /SiO2 towards phenoldegradation under black light irradiationwere investigated and comparedwith undoped TiO2 /SiO2 . The results showed that the photoresponse of Cu2+ and Zn2+doped TiO2 /SiO2were larger than undoped TiO2 /SiO2 , indicating that the photogenerated carrierswere separated more efficiently in Cu2+ and Zn2+doped TiO2 /SiO2 . The reactivitywas in the order of Cu2+ 〉 Zn2+ 〉 Ni2+ 〉 Cr3+ 〉 Co2+ . Thedifferent photoreactivitywas ascribed to combine effect of thedifferent ionic radii and photocorrison tendency of thedopants. The samplewas also characterized by surface analytical methods such as X-raydiffraction, scanning electron micrograph/electrondispersive X-ray analyzer and UV-Vis absorption spectrum.
摘要The paper introduces the preparation of floating TiO2/beads photocalyst attached to the hollow glass micro-beads surface by sol-gel technique using tetrabutyl titanate as material and the preparation of floating CoPcS/TiO2/beads by dip-coatig technique. The optimal factor of degradation of vegetable oil floating on water using CoPcS/TiO2/beads was studied. The result showed that the removal rate of vegetable oil floating on water can highly reach 90% at the optimal condition (acidity or neutrality, 375W medium-pressure mercury vapour lamp, illumination 2h-3h, lg CoPcS/TiO2/beads). The photocatalytic removal efficiency causing by CoPcS/TiO2/beads was increased rapidly by adding a trace amount of H2O2.
基金supported by the National Natural Science Foundation of China (No. 20907022,21003094)the Doctoral Program of Higher Education of China(No. 200800551003,20100032120066)the Special Projects of Environmental Protection (No. 2009ZX07526,2009ZX07208,200909101,2009GJA10021)
摘要Cerium-doped SiO2/TiO2 nanostructured fibers were fabricated by electrospinning technology. The prepared fibers were characterized by thermogravimetric analysis (TGA), scanning electron microscopy (SEM), X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FT-IR). Using the fibers as catalysts, photoeatalytic degradation of Methylene Blue (MB) aqueous solution was carded out under simulated sunlight. The 0.2% Ce doping proved to be the optimal concentration for the doping of TiO2/SiO2, compared to other Ce-doped molar concentrations. The 0.2% Ce-doped SiOdTiO2 fibers exhibited higher photocatalytic activity than industrial Degussa P25 and the samples doped with only Ce or SIO2. The reasons for improving the photocatalytic activity were also discussed. Several operational parameters were studied, which showed that the photocatalytic efficiency of MB was influenced by parameters such as the initial dye concentration, the initial pH, inorganic anions, and so on. In addition, the influences of an electron acceptor and a radical scavenger suggested that OH was the dominant photooxidant during the photocatalytic process. The reuse evaluation of the fibers indicated that their photocatalytic activity had good stability.
基金Supported by the National Natural Science Foundation of China (No. 20473057)Development Foundation of Science and Technology of Shanghai (No. 0352nm094).
摘要TiO2/SiO2 aerogels with different molar ratio of SiO2/TiO2 were prepared via non-supercritical method using tetrabutyl titanate and silica sols as raw materials. The samples were characterized by TEM, SEM, BET, IR, XRD and so on. The results indicate that the BET surface area of TiO2/SiO2 aerogels calcined at 550℃ which consisted of anatase structure of TiO2 with narrow distribution pores of 5-25 nm is as high as 357.89 m2·g-1. For the photocatalytic degradation of pyridine, the catalytic activities of TiO2/SiO2 aerogels are much higher than that of TiO2 powder. The photocatalytic activity of TiO2/SiO2 aerogels calcined at 800℃ is the optimum. The higher the content of SiO2, the higher the photocatalytic activity of TiO2/SiO2 aerogels. The cost for preparation of the aerogels is greatly reduced by using non-supercritical drying method, and the aerogels are hopefully applied in the treatment of industrial waste water such as coking effluent treatment.