Photocatalytic oxidative desulfurization of gasoline in [BMIm]Cu2Cl3 ionic liquid was studied. A 500-W high-pressure mercury lamp was used as the light source for irradiation, nano-TiO2 was used as the photocatalyst a...Photocatalytic oxidative desulfurization of gasoline in [BMIm]Cu2Cl3 ionic liquid was studied. A 500-W high-pressure mercury lamp was used as the light source for irradiation, nano-TiO2 was used as the photocatalyst and air was introduced by a gas pump to supply O2 as the oxidant. Influence of the ratio of V（ionic liquid） to V（oil） and the TiO2 addition on the desulfurization rate of gasoline was investigated. An oxidative kinetics equation was founded. The results showed that the [BMIm]CUECl3 ionic liquid was an effective extractant for the desulfurization of gasoline. The appropriate TiO2 addition was 0.05 g in 50 mL of reaction mixture. The yield of desulfurized gasoline could reach 98.2% after being subjected to reaction for 2 h under the conditions of adopting a ratio of V（ionic liquid）： V（oil）=1：4, an air flow of 100 mL/min and a TiO2 addition dosage of 0.05 g. The kinetics reaction for photo-oxidation of gasoline was a first-order reaction with an apparent rate constant of 1.9664 h^-1 and a half-time of 0.3525 h.展开更多
A novel method to fabricate composition- （IO） films using a positive sacrificial ZnO and topology-controlled ZnO/TiO2 inverse opals IO template has been developed. This method includes a two-step process, preparatio...A novel method to fabricate composition- （IO） films using a positive sacrificial ZnO and topology-controlled ZnO/TiO2 inverse opals IO template has been developed. This method includes a two-step process, preparation of ZnO IO by a simple electrochemical deposition using a self-assembly polystyrene colloidal crystal template and preparation of ZnO/TiO2 IO by a liquid phase deposition （LPD） process at room temperature. The composition and topology of ZnO/TiO2 IO can be easily controlled by changing the duration of the LPD. After 20 min LPD process, a ZnO/TiO2 composite IO with non-close-packed face-centered cubic air sphere array was obtained. Prolonging the duration to 60 min, a pure TiO2 IO （TIO-LPD60） with obviously thickened walls was formed. The formation mechanism for the compositional and topological variation was discussed. A preliminary study on UV photocatalytic property of the samples for degradation of methylene blue reveals that the composition and topology significantly influenced the photocatalytic activity of the IO film. The ZnO/TiO2 composite IO demonstrates a higher degree of activity than both pure ZnO and pure TiO2 IO, although they have a similar IO wall thickness. Moreover, with increasing IO wall thickness from -52 nm to -90 nm, TIO-LPD60 exhibits the highest level of photocatalytic performance.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
Growth of single-crystal Sn O_2 nanowires using a fluorine-doped Sn O_2(FTO) thin film as both the source and substrate is demonstrated for the first time at relatively low temperature(580 °C) which preserves the...Growth of single-crystal Sn O_2 nanowires using a fluorine-doped Sn O_2(FTO) thin film as both the source and substrate is demonstrated for the first time at relatively low temperature(580 °C) which preserves the integrity of the underlying glass support and improves scalability to devices. Furthermore, a microwave hydrothermal process is shown to grow Ti O_2 nanorods on these nanowires to create a hierarchical nanoheterostructure that will lead to efficient photogenerated charge carrier separation and rapid transport of electrons to the substrate. This process simplifies nanowire growth by using commercially available and widely used FTO substrates without the need for an additional upstream Sn source and can be used as a high surface area host structure to many other hierarchical structures.展开更多
The conditions for photocatalytic degradation of ethylenediaminetetraacetic acid (EDTA) in aqueous solution with Fe-doped titanium dioxide (TiO2) were optimized. The degradation efficiencies with Fe-doped TiO2 were be...The conditions for photocatalytic degradation of ethylenediaminetetraacetic acid (EDTA) in aqueous solution with Fe-doped titanium dioxide (TiO2) were optimized. The degradation efficiencies with Fe-doped TiO2 were better, compared with those obtained with bare TiO2 and Pt-doped TiO2. The effect of various experimental factors, such as photocatalytic dosage, temperature, solution pH and light intensity on the photocatalytic degradation of EDTA by Fe-doped TiO2 was investigated. The photocatalytic degradation treatment for the wastewater containing EDTA is simple, easy handling and low cost.展开更多
We have demonstrated a facile and efficient strategy for the fabrication of soluble reduced graphene oxide sheets （RGO） and the preparation of titanium oxide （TiO2） nanoparticle-RGO composites using a modified one...We have demonstrated a facile and efficient strategy for the fabrication of soluble reduced graphene oxide sheets （RGO） and the preparation of titanium oxide （TiO2） nanoparticle-RGO composites using a modified one-step hydrothermal method. It was found that graphene oxide could be easily reduced under solvothermal conditions with ascorbic acid as reductant, with concomitant growth of TiO2 particles on the RGO surface. The TiO2-RGO composite has been thoroughly characterized by Fourier transform infrared spectroscopy, Raman spectroscopy, X-ray diffraction, X-ray photoelectron spectroscopy, and thermogravimetric analysis. Microscopy techniques （scanning electron microscopy, atomic force microscopy, and transmission electron microscopy） have been employed to probe the morphological characteristics as well as to investigate the exfoliation of RGO sheets. The TiOR-RGO composite exhibited excellent photocatalysis of hydrogen evolution.展开更多
A novel rapid and continuous process has developed for the synthesis of nitrogen-doped TiO2（N-TiO2）with flame spray pyrolysis（FSP） method. The nitrogen incorporation into TiO2 was achieved by a facile modification...A novel rapid and continuous process has developed for the synthesis of nitrogen-doped TiO2（N-TiO2）with flame spray pyrolysis（FSP） method. The nitrogen incorporation into TiO2 was achieved by a facile modification（addition of dilute nitric acid） in the precursor for the synthesis. The catalysts were characterized by X-ray diffraction, Raman spectroscopy, transmission electron microscopy, diffuse reflectance spectroscopy, and X-ray photoelectron spectroscopy. The doping of nitrogen into the TiO2 was confirmed by X-ray photoelectron spectroscopy（XPS） and energy dispersive X-ray（EDX） spectroscopy. The UV-vis spectra of the modified catalysts（with primary N source） exhibited band-gap narrowing for 4 N-TiO2 with band gap energy of 2.89 eV, which may be due to the presence of nitrogen in TiO2 structure. The introduction of secondary N-source（urea） into TiO2 crystal lattice results in additional reduction of the band gap energy to 2.68 eV and shows a significant improvement of visible light absorption. The N-TiO2 nanoparticles modified by using secondary N-source showed significant photocatalytic activity under visible light much higher than TiO2. The higher activity is attributed to the synergetic interaction of nitrogen with the TiO2 lattice. The lowering of the band-gap energy for the flame made N-doped TiO2 materials implies that the nitrogen doping in TiO2 by aerosol method is highly effective in extending the optical response of TiO2 in the visible region. The nitrogen atomic percentage has increased monotonically（0.09%-0.15%）with the increase in primary nitrogen source（nitric acid）, and significantly boosted to 0.97% when secondary nitrogen source（urea） was introduced. The highest rate of phenol degradation was obtained for catalysts with secondary N source due to increase in N content in the catalyst.展开更多
Antibacterial cellulose/TiO2 nanoparticles（CTM）, cellulose/ZnO nanoparticles（CZM） and cellulose/ chitosan（CCM） composite membranes were successfully prepared using ionic liquid（IL）, 1-butyl-3-methylimidazo- li...Antibacterial cellulose/TiO2 nanoparticles（CTM）, cellulose/ZnO nanoparticles（CZM） and cellulose/ chitosan（CCM） composite membranes were successfully prepared using ionic liquid（IL）, 1-butyl-3-methylimidazo- lium chloride（[BMIM]C1）, via phase inversion while [BMIM]C1 was recycled through evaporation and used to pre- pare cellulose membrane（CM-RILs）. The pure water flux（PWF） was significantly increased via adding TiO2, ZnO and chitosan to cellulose and a perfect retention value of 67000 bovine serum albumin（BSA） was achieved in all the prepared membranes. The bacterial reduction of cellulose/TiO2 membrane, cellulose/ZnO membrane and cellu- lose/chitosan membrane with a blend ratio of l O：3[m（cellulose）：m（additive）] was the maximum and reached 100%, 100% and 97.2% for S. aureus and 100%, 99.8% and 97.0% for E. coli, respectively. The results demonstrate that cellulose/TiO2 membrane, cellulose/ZnO membrane and celhdose/chitosan membrane can act as good antibacterial materials in water treatment, medical treatment, food industry as well as other applications.展开更多
基金the Research Foundation of Hebei Province Education Department(2007440)
文摘Photocatalytic oxidative desulfurization of gasoline in [BMIm]Cu2Cl3 ionic liquid was studied. A 500-W high-pressure mercury lamp was used as the light source for irradiation, nano-TiO2 was used as the photocatalyst and air was introduced by a gas pump to supply O2 as the oxidant. Influence of the ratio of V（ionic liquid） to V（oil） and the TiO2 addition on the desulfurization rate of gasoline was investigated. An oxidative kinetics equation was founded. The results showed that the [BMIm]CUECl3 ionic liquid was an effective extractant for the desulfurization of gasoline. The appropriate TiO2 addition was 0.05 g in 50 mL of reaction mixture. The yield of desulfurized gasoline could reach 98.2% after being subjected to reaction for 2 h under the conditions of adopting a ratio of V（ionic liquid）： V（oil）=1：4, an air flow of 100 mL/min and a TiO2 addition dosage of 0.05 g. The kinetics reaction for photo-oxidation of gasoline was a first-order reaction with an apparent rate constant of 1.9664 h^-1 and a half-time of 0.3525 h.
文摘A novel method to fabricate composition- （IO） films using a positive sacrificial ZnO and topology-controlled ZnO/TiO2 inverse opals IO template has been developed. This method includes a two-step process, preparation of ZnO IO by a simple electrochemical deposition using a self-assembly polystyrene colloidal crystal template and preparation of ZnO/TiO2 IO by a liquid phase deposition （LPD） process at room temperature. The composition and topology of ZnO/TiO2 IO can be easily controlled by changing the duration of the LPD. After 20 min LPD process, a ZnO/TiO2 composite IO with non-close-packed face-centered cubic air sphere array was obtained. Prolonging the duration to 60 min, a pure TiO2 IO （TIO-LPD60） with obviously thickened walls was formed. The formation mechanism for the compositional and topological variation was discussed. A preliminary study on UV photocatalytic property of the samples for degradation of methylene blue reveals that the composition and topology significantly influenced the photocatalytic activity of the IO film. The ZnO/TiO2 composite IO demonstrates a higher degree of activity than both pure ZnO and pure TiO2 IO, although they have a similar IO wall thickness. Moreover, with increasing IO wall thickness from -52 nm to -90 nm, TIO-LPD60 exhibits the highest level of photocatalytic performance.
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funded by a NASA Space Technology Research Fellowshipa Facilities Grant from the Institute for Materials Research(IMR)at The Ohio State University
文摘Growth of single-crystal Sn O_2 nanowires using a fluorine-doped Sn O_2(FTO) thin film as both the source and substrate is demonstrated for the first time at relatively low temperature(580 °C) which preserves the integrity of the underlying glass support and improves scalability to devices. Furthermore, a microwave hydrothermal process is shown to grow Ti O_2 nanorods on these nanowires to create a hierarchical nanoheterostructure that will lead to efficient photogenerated charge carrier separation and rapid transport of electrons to the substrate. This process simplifies nanowire growth by using commercially available and widely used FTO substrates without the need for an additional upstream Sn source and can be used as a high surface area host structure to many other hierarchical structures.
文摘The conditions for photocatalytic degradation of ethylenediaminetetraacetic acid (EDTA) in aqueous solution with Fe-doped titanium dioxide (TiO2) were optimized. The degradation efficiencies with Fe-doped TiO2 were better, compared with those obtained with bare TiO2 and Pt-doped TiO2. The effect of various experimental factors, such as photocatalytic dosage, temperature, solution pH and light intensity on the photocatalytic degradation of EDTA by Fe-doped TiO2 was investigated. The photocatalytic degradation treatment for the wastewater containing EDTA is simple, easy handling and low cost.
文摘We have demonstrated a facile and efficient strategy for the fabrication of soluble reduced graphene oxide sheets （RGO） and the preparation of titanium oxide （TiO2） nanoparticle-RGO composites using a modified one-step hydrothermal method. It was found that graphene oxide could be easily reduced under solvothermal conditions with ascorbic acid as reductant, with concomitant growth of TiO2 particles on the RGO surface. The TiO2-RGO composite has been thoroughly characterized by Fourier transform infrared spectroscopy, Raman spectroscopy, X-ray diffraction, X-ray photoelectron spectroscopy, and thermogravimetric analysis. Microscopy techniques （scanning electron microscopy, atomic force microscopy, and transmission electron microscopy） have been employed to probe the morphological characteristics as well as to investigate the exfoliation of RGO sheets. The TiOR-RGO composite exhibited excellent photocatalysis of hydrogen evolution.
基金the U.S. EPA/Pegasus contract (contract number EP-C-11-006) for financial support of this work through the scholarship to Siva Nagi Reddy Inturi
文摘A novel rapid and continuous process has developed for the synthesis of nitrogen-doped TiO2（N-TiO2）with flame spray pyrolysis（FSP） method. The nitrogen incorporation into TiO2 was achieved by a facile modification（addition of dilute nitric acid） in the precursor for the synthesis. The catalysts were characterized by X-ray diffraction, Raman spectroscopy, transmission electron microscopy, diffuse reflectance spectroscopy, and X-ray photoelectron spectroscopy. The doping of nitrogen into the TiO2 was confirmed by X-ray photoelectron spectroscopy（XPS） and energy dispersive X-ray（EDX） spectroscopy. The UV-vis spectra of the modified catalysts（with primary N source） exhibited band-gap narrowing for 4 N-TiO2 with band gap energy of 2.89 eV, which may be due to the presence of nitrogen in TiO2 structure. The introduction of secondary N-source（urea） into TiO2 crystal lattice results in additional reduction of the band gap energy to 2.68 eV and shows a significant improvement of visible light absorption. The N-TiO2 nanoparticles modified by using secondary N-source showed significant photocatalytic activity under visible light much higher than TiO2. The higher activity is attributed to the synergetic interaction of nitrogen with the TiO2 lattice. The lowering of the band-gap energy for the flame made N-doped TiO2 materials implies that the nitrogen doping in TiO2 by aerosol method is highly effective in extending the optical response of TiO2 in the visible region. The nitrogen atomic percentage has increased monotonically（0.09%-0.15%）with the increase in primary nitrogen source（nitric acid）, and significantly boosted to 0.97% when secondary nitrogen source（urea） was introduced. The highest rate of phenol degradation was obtained for catalysts with secondary N source due to increase in N content in the catalyst.
文摘Antibacterial cellulose/TiO2 nanoparticles（CTM）, cellulose/ZnO nanoparticles（CZM） and cellulose/ chitosan（CCM） composite membranes were successfully prepared using ionic liquid（IL）, 1-butyl-3-methylimidazo- lium chloride（[BMIM]C1）, via phase inversion while [BMIM]C1 was recycled through evaporation and used to pre- pare cellulose membrane（CM-RILs）. The pure water flux（PWF） was significantly increased via adding TiO2, ZnO and chitosan to cellulose and a perfect retention value of 67000 bovine serum albumin（BSA） was achieved in all the prepared membranes. The bacterial reduction of cellulose/TiO2 membrane, cellulose/ZnO membrane and cellu- lose/chitosan membrane with a blend ratio of l O：3[m（cellulose）：m（additive）] was the maximum and reached 100%, 100% and 97.2% for S. aureus and 100%, 99.8% and 97.0% for E. coli, respectively. The results demonstrate that cellulose/TiO2 membrane, cellulose/ZnO membrane and celhdose/chitosan membrane can act as good antibacterial materials in water treatment, medical treatment, food industry as well as other applications.
