Iron(Ⅲ)-doped nanostructure TiO2-coated SiO2 (TiO2/SiO2) particles were prepared using the layer-by-layer assembly technique and their photocatalytic property was studied. TiO2 colloids were synthesized employing...Iron(Ⅲ)-doped nanostructure TiO2-coated SiO2 (TiO2/SiO2) particles were prepared using the layer-by-layer assembly technique and their photocatalytic property was studied. TiO2 colloids were synthesized employing the sol-gel method with TiChas a precursor. The samples were characterized by Fourier transform infrared spectroscopy (FTIR), SEM, EDS, XPS, and XRD. The experimental results show that TiO2 nanopowders on the surface of SiO2 particles are well distributed, the amount of TiO2 is increased with the adding of coating layers, the pure anatase-TiO2 coating layers are synthesized at 500℃, and the photocatalytic activity of Fe^3+-doped TiO2/SiO2 is higher than that of undoped TiO2/SiO2.展开更多
A new upconversion luminescence agent, 40CdF2·60BaF2·0.8ErO3, was synthesized and its fluorescent spectra were determined. This upconversion luminescence agent can emit five upconversion fluorescent peaks sh...A new upconversion luminescence agent, 40CdF2·60BaF2·0.8ErO3, was synthesized and its fluorescent spectra were determined. This upconversion luminescence agent can emit five upconversion fluorescent peaks shown in the fluorescent spectra whose wavelengths are all below 387 nm under the excitation of 488 nm visible light. This upconversion luminescence agent was mixed into nano rutile TiO2 powder by ultrasonic and boiling dispersion and the novel doped nano TiO2 photocatalyst utilizing visible light was firstly prepared. The doped TiO2 powder was charactered by XRD and TEM and its photocatalytic activity was tested through the photocatalytic degradation of methyl orange as a model compound under the visible light irradiation emitted by six three basic color lamps. In order to compare the photocatalytic activities, the same experiment was carried out for undoped TiO2 powder. The degradation ratio of methyl orange in the presence of doped nano TiO2 powder reached 32.5% under visible light irradiation at 20 h which was obviously higher than the corresponding 1.64% in the presence of undoped nano TiO2 powder, which indicate the upconversion luminescence agent prepared as dopant can effectively turn visible lights to ultraviolet lights that are absorbed by nano TiO2 particles to produce the electron-cavity pairs. All the results show that the nano rutile TiO2 powder doped with upconversion luminescence agent is a promising photocatalyst using sunlight for treating the industry dye wastewater in great force.展开更多
A new kind of emulsion containing nano TiO_2 was developed through the dispersion experiment. A commercial emulsion and a prepared by our lab emulsion without nano particles were chosen as controls to test the tribolo...A new kind of emulsion containing nano TiO_2 was developed through the dispersion experiment. A commercial emulsion and a prepared by our lab emulsion without nano particles were chosen as controls to test the tribological and antibacterial properties of this new emulsion. The load carrying capacity, friction coefficient and average diameter of wear scars were tested by a four-ball machine and the comprehensive antifriction parameter ω was calculated. The wetting angle was also tested using a JC200C1 wetting angle tester. The micro surface and roughness of rolled strips were analyzed to investigate the tribological performance of the recommended new emulsion in strip production. It is shown that the new nano-emulsion possesses a higher load carrying capacity and wetting ability. Therefore the abrasive/plowing wear is reduced more efficiently with the addition of nano particles, and the micro surface is improved. The density of bacteria in the emulsions was tested after the cold rolling experiment. The emulsion breaking ratio and bacteria density were also tested in different time intervals after the cold rolling experiment. The final p H values and bacteria density of different layers of emulsions were measured and the sediment was analyzed by TEM to evaluate the antibacterial behavior of this new emulsion. It is shown that the density of microbial colonies which led to a corruption of emulsions was decreased about 90% and the effective antibacterial period was prolonged.展开更多
Nano-sized titania powders have been prepared by hydrolysis of tetrabutyl titanate in the droplet of water/OP-7/pentanol/cyclohexane microemulsion system.The effects of ingredient change on the water drop size and par...Nano-sized titania powders have been prepared by hydrolysis of tetrabutyl titanate in the droplet of water/OP-7/pentanol/cyclohexane microemulsion system.The effects of ingredient change on the water drop size and particle size were investigated.The prepared TiO_2 was in the form of anatase after annealing.TiO_2 was characterized by TG-TGA, FTIR,XRD to measure the transformation temperature,surface adsorption and average size.展开更多
The dynamic wetting of water spreading on TiO 2 and TiO 2 SiO 2 films prepared by sol gel method and subsequently treated by air plasma and UV irradiation was investigated. Water completely spread on TiO 2 surface wit...The dynamic wetting of water spreading on TiO 2 and TiO 2 SiO 2 films prepared by sol gel method and subsequently treated by air plasma and UV irradiation was investigated. Water completely spread on TiO 2 surface within 3 s and its dynamic contact angles can be expressed by a power law θ d= k(t+a) -n with the n value 0.98. Less than 50%(molar fraction) SiO 2 addition can accelerate the dynamic water spreading rate on the TiO 2 SiO 2 films and the optimum molar fraction of SiO 2 amount corresponding to as annealed, air plasma, and UV irradiation treatment process is 15%, 10% and 20%, respectively.展开更多
A series of SO 2- 4/TiO 2 SiO 2 catalysts with different mass fractions of SiO 2 were prepared by sol gel method. The effect of adding SiO 2 on the crystal structure, specific surface area, oxygen adsorption, and acid...A series of SO 2- 4/TiO 2 SiO 2 catalysts with different mass fractions of SiO 2 were prepared by sol gel method. The effect of adding SiO 2 on the crystal structure, specific surface area, oxygen adsorption, and acidity of SO 2- 4/TiO 2 catalyst and its photocatalytic property for degradation of bromomethane was studied. The results showed that the specific surface area and amount of oxygen adsorption of catalyst were increased by addition of SiO 2, leading to the obvious increase on photocatalytic activity of SO 2- 4/TiO 2 SiO 2 catalysts and mineralization ratio of bromomethane. Comparing with SO 2- 4/TiO 2, the acidic strength and anti moisture ability of SO 2- 4/TiO 2 SiO 2 catalyst were decreased.展开更多
基金the Nationnal Natural Science Foundation of China (No. 50342016).
文摘Iron(Ⅲ)-doped nanostructure TiO2-coated SiO2 (TiO2/SiO2) particles were prepared using the layer-by-layer assembly technique and their photocatalytic property was studied. TiO2 colloids were synthesized employing the sol-gel method with TiChas a precursor. The samples were characterized by Fourier transform infrared spectroscopy (FTIR), SEM, EDS, XPS, and XRD. The experimental results show that TiO2 nanopowders on the surface of SiO2 particles are well distributed, the amount of TiO2 is increased with the adding of coating layers, the pure anatase-TiO2 coating layers are synthesized at 500℃, and the photocatalytic activity of Fe^3+-doped TiO2/SiO2 is higher than that of undoped TiO2/SiO2.
基金The National Natural Science Foundation of China (No.20371023)
文摘A new upconversion luminescence agent, 40CdF2·60BaF2·0.8ErO3, was synthesized and its fluorescent spectra were determined. This upconversion luminescence agent can emit five upconversion fluorescent peaks shown in the fluorescent spectra whose wavelengths are all below 387 nm under the excitation of 488 nm visible light. This upconversion luminescence agent was mixed into nano rutile TiO2 powder by ultrasonic and boiling dispersion and the novel doped nano TiO2 photocatalyst utilizing visible light was firstly prepared. The doped TiO2 powder was charactered by XRD and TEM and its photocatalytic activity was tested through the photocatalytic degradation of methyl orange as a model compound under the visible light irradiation emitted by six three basic color lamps. In order to compare the photocatalytic activities, the same experiment was carried out for undoped TiO2 powder. The degradation ratio of methyl orange in the presence of doped nano TiO2 powder reached 32.5% under visible light irradiation at 20 h which was obviously higher than the corresponding 1.64% in the presence of undoped nano TiO2 powder, which indicate the upconversion luminescence agent prepared as dopant can effectively turn visible lights to ultraviolet lights that are absorbed by nano TiO2 particles to produce the electron-cavity pairs. All the results show that the nano rutile TiO2 powder doped with upconversion luminescence agent is a promising photocatalyst using sunlight for treating the industry dye wastewater in great force.
基金supported by the National Natural Science Foundation of China (contract/grant number: 51274037) affiliated to the project: "The research of lubrication model and interaction between nano-lubricating particles and rolling deformed surface."
文摘A new kind of emulsion containing nano TiO_2 was developed through the dispersion experiment. A commercial emulsion and a prepared by our lab emulsion without nano particles were chosen as controls to test the tribological and antibacterial properties of this new emulsion. The load carrying capacity, friction coefficient and average diameter of wear scars were tested by a four-ball machine and the comprehensive antifriction parameter ω was calculated. The wetting angle was also tested using a JC200C1 wetting angle tester. The micro surface and roughness of rolled strips were analyzed to investigate the tribological performance of the recommended new emulsion in strip production. It is shown that the new nano-emulsion possesses a higher load carrying capacity and wetting ability. Therefore the abrasive/plowing wear is reduced more efficiently with the addition of nano particles, and the micro surface is improved. The density of bacteria in the emulsions was tested after the cold rolling experiment. The emulsion breaking ratio and bacteria density were also tested in different time intervals after the cold rolling experiment. The final p H values and bacteria density of different layers of emulsions were measured and the sediment was analyzed by TEM to evaluate the antibacterial behavior of this new emulsion. It is shown that the density of microbial colonies which led to a corruption of emulsions was decreased about 90% and the effective antibacterial period was prolonged.
文摘Nano-sized titania powders have been prepared by hydrolysis of tetrabutyl titanate in the droplet of water/OP-7/pentanol/cyclohexane microemulsion system.The effects of ingredient change on the water drop size and particle size were investigated.The prepared TiO_2 was in the form of anatase after annealing.TiO_2 was characterized by TG-TGA, FTIR,XRD to measure the transformation temperature,surface adsorption and average size.
文摘The dynamic wetting of water spreading on TiO 2 and TiO 2 SiO 2 films prepared by sol gel method and subsequently treated by air plasma and UV irradiation was investigated. Water completely spread on TiO 2 surface within 3 s and its dynamic contact angles can be expressed by a power law θ d= k(t+a) -n with the n value 0.98. Less than 50%(molar fraction) SiO 2 addition can accelerate the dynamic water spreading rate on the TiO 2 SiO 2 films and the optimum molar fraction of SiO 2 amount corresponding to as annealed, air plasma, and UV irradiation treatment process is 15%, 10% and 20%, respectively.
文摘A series of SO 2- 4/TiO 2 SiO 2 catalysts with different mass fractions of SiO 2 were prepared by sol gel method. The effect of adding SiO 2 on the crystal structure, specific surface area, oxygen adsorption, and acidity of SO 2- 4/TiO 2 catalyst and its photocatalytic property for degradation of bromomethane was studied. The results showed that the specific surface area and amount of oxygen adsorption of catalyst were increased by addition of SiO 2, leading to the obvious increase on photocatalytic activity of SO 2- 4/TiO 2 SiO 2 catalysts and mineralization ratio of bromomethane. Comparing with SO 2- 4/TiO 2, the acidic strength and anti moisture ability of SO 2- 4/TiO 2 SiO 2 catalyst were decreased.