The TiO2 thin films were prepared on the surface of soda lime glass via sol gel method, and calcined at 500℃ for 2h. The as calcined TiO2 thin films were treated in 1mol·L-1 H2SO4 aqueous solution for 24h, after...The TiO2 thin films were prepared on the surface of soda lime glass via sol gel method, and calcined at 500℃ for 2h. The as calcined TiO2 thin films were treated in 1mol·L-1 H2SO4 aqueous solution for 24h, after that the thin films were heat treated at 100℃ and 500℃ for 0.5h, respectively. The structures and photocatalytic activity of TiO2 thin films before and after surface acid treatment were characterized and evaluated by UV Vis, SEM, TEM and XPS and photocatalytic decoloration of methyl orange aqueous solution, respectively. It was found that after TiO2 thin films were treated in H2SO4 solution and calcined at 100℃ and 500℃, the content of sodium ions in the TiO2 thin films decreases and the photocatalytic activity of the thin films increases obviously. Moreover, the films show the highest photocatalytic activity at 500℃.展开更多
Tailored synthesis of well-defined anatase TiO2-based crystals with exposed {001} facets has stimulated incessant research interest worldwide due to their scientific and technological importance. Herein, anatase nitro...Tailored synthesis of well-defined anatase TiO2-based crystals with exposed {001} facets has stimulated incessant research interest worldwide due to their scientific and technological importance. Herein, anatase nitrogen-doped TiO2 （N-TiO2） nanoparticles with exposed {001} facets deposited on the graphene （GR） sheets （N-TiO2-001/GR） were synthesized for the first time via a one-step solvothermal synthetic route using NH4F as the morphology-controlling agent. The experimental results exemplified that GR was uniformly covered with anatase N-TiO2 nanoparticles （10-17 nm）, exposing the {001} facets. The percentage of exposed {001} facets in the N-TiO2-001/GR nanocomposites was calculated to be ca. 35%. Also, a red shift in the absorption edge and a strong absorption in the visible light range were observed due to the formation of Ti-O-C bonds, resulting in the successful narrowing of the band gap from 3.23 to 2.9 eV. The photocatalytic activities of the as-prepared photocatalysts were evaluated for CO2 reduction to produce CH, in the presence of water vapor under ambient temperature and atmospheric pressure using a low-power 15 W energy-saving daylight lamp as the visible light source--in contrast to the most commonly employed high-power xenon lamps--which rendered the process economically and practically feasible. Among all the studied photocatalysts, the N-TiO2-001/GR nanocomposites exhibited the greatest CH4 yield of 3.70 p-mol＇gcatalyst 1, approxi- mately 11-fold higher activity than the TiO2-001. The enhancement of photocatalyfic performance was ascribed to the effective charge anti-recombination of graphene, high absorption of visible light region relative to the {101} facets. and high catalytic activity of {001} facets展开更多
TiO2/glass film was prepared by a solgel method with titanium tetrabutoxide as precursor,and used in photocatalytic degradation of 4Chlorophenol(4CP)in aqueous solution.The crystal type and size of TiO2 in f...TiO2/glass film was prepared by a solgel method with titanium tetrabutoxide as precursor,and used in photocatalytic degradation of 4Chlorophenol(4CP)in aqueous solution.The crystal type and size of TiO2 in film prepared in different experimental conditions were characterized by using XRD.The experiments indicated that the TiO2 particles in different film appear regular anatase structure with size about 833nm after heating treatment at 500℃ temperature,and the film coated 5 layers of TiO2 sol in the case of higher(pH≥10)and lower pH value(pH≤2) showed a higher catalytic activity.The relationship between initial 4CP concentration(C0) and reaction rate(r0) follow LangmuirHinshelwood equation,and the photocatalytic degradation of 4CP(C0≤07mmol·L-1)can be expressed by first order kinetics.展开更多
An analytical method based on TiO2 nanotubes solid-phase extraction （SPE） combined with gas chromatography （GC） was established for the analysis of seven polycyclic aromatic hydrocarbons （PAHs）： acenaphtylene, ...An analytical method based on TiO2 nanotubes solid-phase extraction （SPE） combined with gas chromatography （GC） was established for the analysis of seven polycyclic aromatic hydrocarbons （PAHs）： acenaphtylene, acenaphthene, anthracene, fluorene, phenanthrene, fluoranthene and pyrene. Factors affecting the extraction efficiency including the eluent type and its volume, adsorbent amount, sample volume, sample pH and sample flow rate were optimized. The characteristic data of analytical performance were determined to investigate the sensitivity and precision of the method. Under the optimized extraction conditions, the method showed good linearity in the range of 0.01-0.8 μg/mL, repeatability of the extraction （RSD were between 6.7% and 13.5%, n = 5） and satisfactory detection limits （0.017-0.059 μg/mL）. The developed method was successfully applied to the analysis of surface water （tap, river and dam） samples. The recoveries of PAHs spiked in environmental water samples ranged from 90% to 100%. All the results indicated the potential application of titanate nanotubes as solid-phase extraction adsorbents to pre-treat water samples.展开更多
文摘The TiO2 thin films were prepared on the surface of soda lime glass via sol gel method, and calcined at 500℃ for 2h. The as calcined TiO2 thin films were treated in 1mol·L-1 H2SO4 aqueous solution for 24h, after that the thin films were heat treated at 100℃ and 500℃ for 0.5h, respectively. The structures and photocatalytic activity of TiO2 thin films before and after surface acid treatment were characterized and evaluated by UV Vis, SEM, TEM and XPS and photocatalytic decoloration of methyl orange aqueous solution, respectively. It was found that after TiO2 thin films were treated in H2SO4 solution and calcined at 100℃ and 500℃, the content of sodium ions in the TiO2 thin films decreases and the photocatalytic activity of the thin films increases obviously. Moreover, the films show the highest photocatalytic activity at 500℃.
文摘Tailored synthesis of well-defined anatase TiO2-based crystals with exposed {001} facets has stimulated incessant research interest worldwide due to their scientific and technological importance. Herein, anatase nitrogen-doped TiO2 （N-TiO2） nanoparticles with exposed {001} facets deposited on the graphene （GR） sheets （N-TiO2-001/GR） were synthesized for the first time via a one-step solvothermal synthetic route using NH4F as the morphology-controlling agent. The experimental results exemplified that GR was uniformly covered with anatase N-TiO2 nanoparticles （10-17 nm）, exposing the {001} facets. The percentage of exposed {001} facets in the N-TiO2-001/GR nanocomposites was calculated to be ca. 35%. Also, a red shift in the absorption edge and a strong absorption in the visible light range were observed due to the formation of Ti-O-C bonds, resulting in the successful narrowing of the band gap from 3.23 to 2.9 eV. The photocatalytic activities of the as-prepared photocatalysts were evaluated for CO2 reduction to produce CH, in the presence of water vapor under ambient temperature and atmospheric pressure using a low-power 15 W energy-saving daylight lamp as the visible light source--in contrast to the most commonly employed high-power xenon lamps--which rendered the process economically and practically feasible. Among all the studied photocatalysts, the N-TiO2-001/GR nanocomposites exhibited the greatest CH4 yield of 3.70 p-mol＇gcatalyst 1, approxi- mately 11-fold higher activity than the TiO2-001. The enhancement of photocatalyfic performance was ascribed to the effective charge anti-recombination of graphene, high absorption of visible light region relative to the {101} facets. and high catalytic activity of {001} facets
文摘TiO2/glass film was prepared by a solgel method with titanium tetrabutoxide as precursor,and used in photocatalytic degradation of 4Chlorophenol(4CP)in aqueous solution.The crystal type and size of TiO2 in film prepared in different experimental conditions were characterized by using XRD.The experiments indicated that the TiO2 particles in different film appear regular anatase structure with size about 833nm after heating treatment at 500℃ temperature,and the film coated 5 layers of TiO2 sol in the case of higher(pH≥10)and lower pH value(pH≤2) showed a higher catalytic activity.The relationship between initial 4CP concentration(C0) and reaction rate(r0) follow LangmuirHinshelwood equation,and the photocatalytic degradation of 4CP(C0≤07mmol·L-1)can be expressed by first order kinetics.
文摘An analytical method based on TiO2 nanotubes solid-phase extraction （SPE） combined with gas chromatography （GC） was established for the analysis of seven polycyclic aromatic hydrocarbons （PAHs）： acenaphtylene, acenaphthene, anthracene, fluorene, phenanthrene, fluoranthene and pyrene. Factors affecting the extraction efficiency including the eluent type and its volume, adsorbent amount, sample volume, sample pH and sample flow rate were optimized. The characteristic data of analytical performance were determined to investigate the sensitivity and precision of the method. Under the optimized extraction conditions, the method showed good linearity in the range of 0.01-0.8 μg/mL, repeatability of the extraction （RSD were between 6.7% and 13.5%, n = 5） and satisfactory detection limits （0.017-0.059 μg/mL）. The developed method was successfully applied to the analysis of surface water （tap, river and dam） samples. The recoveries of PAHs spiked in environmental water samples ranged from 90% to 100%. All the results indicated the potential application of titanate nanotubes as solid-phase extraction adsorbents to pre-treat water samples.
