The iron doping titanium dioxide was prepared by sol-gel,step precipitation,co-precipitation and immersion methods,respectively.The photocatalytic activities of these prepared samples were evaluated in X-3B dispersion...The iron doping titanium dioxide was prepared by sol-gel,step precipitation,co-precipitation and immersion methods,respectively.The photocatalytic activities of these prepared samples were evaluated in X-3B dispersion irradiated under UV.The experimental results showed that the immersion method,especially using the nano TiO2 as immersion matrix,greatly enhanced the photocatalytic activity.One fold enhancement in photocatalytic activity was observed in the case of the sample prepared by immersion doping method.This may be attributed to the nano-size effect,the irreversible hole trapper in non-saturated bonding field of Fe3＋ and larger lattice strain.展开更多
The ultrafine V 2O 5 TiO 2 composite oxide particles have been prepared by the high energy ball milling method and characterized by X ray diffraction, transmission electron microscopy, laser Raman spectroscopy, temper...The ultrafine V 2O 5 TiO 2 composite oxide particles have been prepared by the high energy ball milling method and characterized by X ray diffraction, transmission electron microscopy, laser Raman spectroscopy, temperature programmed reduction, and microreactor testing. It has been shown that the milling process induces the formation of ultrafine V 2O 5 TiO 2 composite oxide particles with dispersed vanadium oxide on the surface of anatase TiO 2, accompanied by a decrease in particle size of V 2O 5 and TiO 2. The TPR results indicate that the strong interaction between dispersed V O species and TiO 2 increases the reducibility of the vanadium oxide. The catalytic properties of the catalysts for the selective oxidation of o xylene were evaluated. Under the similar o xylene conversion (58%), the ultrafine V 2O 5 TiO 2 composite oxide catalyst exhibits a higher selectivity for phthalic anhydride (44%) than the catalyst prepared by the conventional impregnation method (23%), and the catalyst composition has a great influence on the catalytic properties.展开更多
文摘The iron doping titanium dioxide was prepared by sol-gel,step precipitation,co-precipitation and immersion methods,respectively.The photocatalytic activities of these prepared samples were evaluated in X-3B dispersion irradiated under UV.The experimental results showed that the immersion method,especially using the nano TiO2 as immersion matrix,greatly enhanced the photocatalytic activity.One fold enhancement in photocatalytic activity was observed in the case of the sample prepared by immersion doping method.This may be attributed to the nano-size effect,the irreversible hole trapper in non-saturated bonding field of Fe3＋ and larger lattice strain.
文摘The ultrafine V 2O 5 TiO 2 composite oxide particles have been prepared by the high energy ball milling method and characterized by X ray diffraction, transmission electron microscopy, laser Raman spectroscopy, temperature programmed reduction, and microreactor testing. It has been shown that the milling process induces the formation of ultrafine V 2O 5 TiO 2 composite oxide particles with dispersed vanadium oxide on the surface of anatase TiO 2, accompanied by a decrease in particle size of V 2O 5 and TiO 2. The TPR results indicate that the strong interaction between dispersed V O species and TiO 2 increases the reducibility of the vanadium oxide. The catalytic properties of the catalysts for the selective oxidation of o xylene were evaluated. Under the similar o xylene conversion (58%), the ultrafine V 2O 5 TiO 2 composite oxide catalyst exhibits a higher selectivity for phthalic anhydride (44%) than the catalyst prepared by the conventional impregnation method (23%), and the catalyst composition has a great influence on the catalytic properties.
