The immobilized photocatalyst, TiO2 film supported on activated carbon fibers (TiO2/ACFs) prepared with molecular adsorption-deposition (MAD), exhibits high stability in cyclic photodegradation runs. The interposition...The immobilized photocatalyst, TiO2 film supported on activated carbon fibers (TiO2/ACFs) prepared with molecular adsorption-deposition (MAD), exhibits high stability in cyclic photodegradation runs. The interposition fixing structure between TiO2 film and carbon fiber was investigated by means of SEM-EDX, XRD, XPS and FTIR, and a model was proposed to explain this structure. With SEM examination of carbon fiber surface after removing the deposited TiO2 film, a residual TiO2 super-thin film was found to exist still. By determining surface groups on ACFs, titanium sulfate (Ti2(SO4)3) in burnt remainders of the TiO2/ACFs was thought to be formed with an interfacial reaction between TiO2 film and carbon fibers. These provide some evidence of firm attachment of TiO2 film to carbon fiber surface. In the consideration of characteristics of the MAD, the deposition mechanism of TiO2 film on ACFs was proposed, and the interposition fixing structure was inferred to intercrossedly form between TiO2 film and ACFs’ surface. This structure leaded to firm attachment and high stability of the TiO2 film.展开更多
Uniform crystalline TiO2 thin films were coated on silica glass fibers by liquid phase deposition from aqueous solution of ammonium hexafluorotitanate at low temperature. TiO2 thin films and nanopowders were prepared ...Uniform crystalline TiO2 thin films were coated on silica glass fibers by liquid phase deposition from aqueous solution of ammonium hexafluorotitanate at low temperature. TiO2 thin films and nanopowders were prepared by adding H3BO3 into （NH4）2TiF6 solution supersaturated with anatase nano-crystalline TiO2 at 40 ℃. The effects of the deposition conditions on the surface morphology, section morphology, thickness of the deposited TiO2 thin films were investigated. The results indicate that the growth rate and particle size of the thin films were controlled by both the deposition conditions and the amount of anatase nano-crystalline TiO2.展开更多
TiO_2 nanoparticles coated cotton fiber composite was successfully prepared by using a sol-gel method at low temperature(about 100℃) using tetrabutyl-titanate [Ti(OBu)_4] as raw material.The preparation of the TiO_2 ...TiO_2 nanoparticles coated cotton fiber composite was successfully prepared by using a sol-gel method at low temperature(about 100℃) using tetrabutyl-titanate [Ti(OBu)_4] as raw material.The preparation of the TiO_2 colloid and the composite were described.The properties of resulting materials were characterized by SEM and XRD,the photocatalytic degradation performance was tested using methylene blue(MB) as the target pollutant in aqueous solution.The results showed that the amorphous TiO_2 nanoparticles were distributed evenly on the outer surfaces of cotton fibers,which shows efficient photocatalytic properties when exposed to UV light,the degradation rate of MB reached 95.35% under the conditions of catalyst dosage 2.5 g/L,MB concentration 50 mg/L,irradiation time 120 min,and pH 10,and the photocatalytic activity of TiO_2/cotton fibers remained above 90% of its activity as-prepared after being used four times,the degradation rate of MB could reach 88.78% when irradiation time was 120 min.The photocatalytic degradation of MB could be properly described by the first-order kinetic law.By comparison of the removal rates of MB with and without UV light,it could be affirmed that the disappearance of MB was due to photodegradation rather than adsorption on cotton fibers.展开更多
基金ACKNOWLEDGMENTS This work was supported by the National Natural Science Foundation of China （No.41373127） and Liaon- ing Provincial Natural Science Foundation of China （No.2013020121）.
文摘The immobilized photocatalyst, TiO2 film supported on activated carbon fibers (TiO2/ACFs) prepared with molecular adsorption-deposition (MAD), exhibits high stability in cyclic photodegradation runs. The interposition fixing structure between TiO2 film and carbon fiber was investigated by means of SEM-EDX, XRD, XPS and FTIR, and a model was proposed to explain this structure. With SEM examination of carbon fiber surface after removing the deposited TiO2 film, a residual TiO2 super-thin film was found to exist still. By determining surface groups on ACFs, titanium sulfate (Ti2(SO4)3) in burnt remainders of the TiO2/ACFs was thought to be formed with an interfacial reaction between TiO2 film and carbon fibers. These provide some evidence of firm attachment of TiO2 film to carbon fiber surface. In the consideration of characteristics of the MAD, the deposition mechanism of TiO2 film on ACFs was proposed, and the interposition fixing structure was inferred to intercrossedly form between TiO2 film and ACFs’ surface. This structure leaded to firm attachment and high stability of the TiO2 film.
文摘Uniform crystalline TiO2 thin films were coated on silica glass fibers by liquid phase deposition from aqueous solution of ammonium hexafluorotitanate at low temperature. TiO2 thin films and nanopowders were prepared by adding H3BO3 into （NH4）2TiF6 solution supersaturated with anatase nano-crystalline TiO2 at 40 ℃. The effects of the deposition conditions on the surface morphology, section morphology, thickness of the deposited TiO2 thin films were investigated. The results indicate that the growth rate and particle size of the thin films were controlled by both the deposition conditions and the amount of anatase nano-crystalline TiO2.
基金Supported by Foundation of Educational Bureau of Liaoning Province (No2008573)
文摘TiO_2 nanoparticles coated cotton fiber composite was successfully prepared by using a sol-gel method at low temperature(about 100℃) using tetrabutyl-titanate [Ti(OBu)_4] as raw material.The preparation of the TiO_2 colloid and the composite were described.The properties of resulting materials were characterized by SEM and XRD,the photocatalytic degradation performance was tested using methylene blue(MB) as the target pollutant in aqueous solution.The results showed that the amorphous TiO_2 nanoparticles were distributed evenly on the outer surfaces of cotton fibers,which shows efficient photocatalytic properties when exposed to UV light,the degradation rate of MB reached 95.35% under the conditions of catalyst dosage 2.5 g/L,MB concentration 50 mg/L,irradiation time 120 min,and pH 10,and the photocatalytic activity of TiO_2/cotton fibers remained above 90% of its activity as-prepared after being used four times,the degradation rate of MB could reach 88.78% when irradiation time was 120 min.The photocatalytic degradation of MB could be properly described by the first-order kinetic law.By comparison of the removal rates of MB with and without UV light,it could be affirmed that the disappearance of MB was due to photodegradation rather than adsorption on cotton fibers.
