ZrO2/TiO2 composite photocatalytic film was produced on the pure titanium substrate using in-situ Zr（OH）4 colloidal particle by the micro-arc oxidation technique and characterized by scanning electron microscope （...ZrO2/TiO2 composite photocatalytic film was produced on the pure titanium substrate using in-situ Zr（OH）4 colloidal particle by the micro-arc oxidation technique and characterized by scanning electron microscope （SEM）, energy dispersive X-ray （EDX）, X-ray diffraction （XRD） and ultraviolet-visible （UV-Vis） spectrophotometer. The composite film shows a lamellar and porous structure which consists of anatase, futile and ZrO2 phases. The optical absorption edge of film is shifted to longer wavelength when ZrO2 is introduced to TiO2. Furthermore, the photocatalytic reaction rate constants of degradation of rhodamine B solution with ZrO2/TiO2 composite film and pure TiO2 film under ultraviolet irradiation are measured as 0.0442 and 0.0186 h 1, respectively.展开更多
Series of TiO 2-ZnO heterojunction composite films with different n（Zn）/n（Ti） ratios were prepared by UDP450 magnetron sputter ion plating equipment, and the mole ratio of Zn to Ti was controlled by adjusting the ...Series of TiO 2-ZnO heterojunction composite films with different n（Zn）/n（Ti） ratios were prepared by UDP450 magnetron sputter ion plating equipment, and the mole ratio of Zn to Ti was controlled by adjusting the current values of sputtering target. The effects of n（Zn）/n（Ti） on the microstructures of TiO2-ZnO films were investigated by SEM, AFM, Raman and XPS, and their photocatalytic decomposition of methyl orange solutions was evaluated. The results show that an increase in n（Zn）/n（Ti） typically results in a decrease in the grain size of composite films firstly and then an increase of grain size, while an increase in n（Zn）/n（Ti） leads to an increase in film roughness firstly and then a decrease in film roughness. Both grain size and roughness of TiO2-ZnO films reach the maximum and minimum at n（Zn）/n（Ti） of 1/9.3, respectively. The n（Zn）/n（Ti） shows little effect on the valences of Zn and Ti elements, which mainly exist in the form of TiO2 and ZnO phases. The n（Zn）/n（Ti） has influence on the amount of anatase/rutile TiO2 heterojunction in the film. With increase of the n（Zn）/n（Ti）, the absorption intensity of the composite film increases and the absorption region extends to 450 nm, which is redshifted as much as 150 nm in comparison with the pure TiO2 films. However, the photocatalytic abilities of heterogeneous composite films do not depend on the n（Zn）/n（Ti） but rather on the microstructures of the TiO2-ZnO composite films. Degradation rate of the film reaches the maximum and the photocatalytic decomposition of pollutants works best when n（Zn）/n（Ti）=1：9.3.展开更多
The Ni-P/TiO2 composite film on sintered NdFeB permanent magnet was investigated by X-ray diffraction （XRD）,environmental scanning electron microscopy （ESEM）,and energy dispersive X-ray spectrometer （EDX）. The c...The Ni-P/TiO2 composite film on sintered NdFeB permanent magnet was investigated by X-ray diffraction （XRD）,environmental scanning electron microscopy （ESEM）,and energy dispersive X-ray spectrometer （EDX）. The corrosion resistance of Ni-P/TiO2 film coated on NdFeB magnet,in 0.5 mol/L NaCl solution,was studied by potentiodynamic polarization,salt spray test and electrochemical impedance spectroscopy （EIS） techniques. The self-corrosion current density （icorr） and the polarization resistance （Rp） of Ni-P/TiO2 film are 0.22 μA/cm2 （about 14% of that of Ni-P coating）,and 120 kΩ·cm2 （about 2 times of that of Ni-P coating）,respectively. The anti-salt spray time of Ni-P/TiO2 film is about 2.5 times of that of the Ni-P coating. The results indicate that Ni-P/TiO2 film has a better corrosion resistance than Ni-P coating,and the composite film increases the corrosion resistance of NdFeB magnet markedly.展开更多
Cu2O/TiOa/Pt three-layer films were deposited on glass substrates using magnetron sputtering method. The surface morphology and the optical properties of the composite film were characterized by X-ray diffraction （XR...Cu2O/TiOa/Pt three-layer films were deposited on glass substrates using magnetron sputtering method. The surface morphology and the optical properties of the composite film were characterized by X-ray diffraction （XRD）, scanning electron microscopy （SEM）, ultraviolet- visible spectroscopy （UV-Vis） and photoluminescence spectroscopy （PL）. The photocatalytic activity of the samples was evaluated by the photocatalytic degradation of methyl orange （MO） aqueous solution under visible light irradiation. The results indicate that the Cu2O/TiO2/Pt composite films are made up of three layers which are Pt layer, anatase-TiO2 layer and Cu2O layer from bottom to top. The surface of the films is even and composed of regular-shaped spherical particles. The photocatalytic activity of the Cu2O/TiO2/Pt three-layer film is much higher than that of the Cu2O/TiO2 double-layer film. Such enhancement is ascribed to the presence of Pt layer, which further inhibits the photogenerated electron-hole recombination, prolongs the lifetime of the photogenerated carriers, increases the quantum efficiency and hence improves the photocatalytic activity of the film effectively.展开更多
A NiP/TiO2 composite film on carbon steel was prepared by electroless plating and sol-gel composite process. An artificial neural network was applied to optimize the prepared condition of the composite film. Corrosion...A NiP/TiO2 composite film on carbon steel was prepared by electroless plating and sol-gel composite process. An artificial neural network was applied to optimize the prepared condition of the composite film. Corrosion behavior of the NiP/TiO2 composite film was investigated by polarization resistance measurement, anode polarization, ESEM （environmental scanning electron microscopy） and EIS （electrochemical impedance spectroscopy） measurements. Results showed that the NiP/ TiO2 composite film has a good corrosion resistance in 0.5mol/L H2SO4 solution. The element valence of the composite film was characterized by XPS （X-ray photoelectron spectroscopy） spectrum, and an anticorrosion mechanism of the composite film was discussed.展开更多
In this work, TiO2/Ti composite films were fabricated by 2-setp MCT and the following high temperature oxidation. Antibacterial activity of the composite films treated by ultrasonic cleaning to increase the performanc...In this work, TiO2/Ti composite films were fabricated by 2-setp MCT and the following high temperature oxidation. Antibacterial activity of the composite films treated by ultrasonic cleaning to increase the performance reliability was examined. The prepared TiO2/Ti composite films showed high photocatalytic activity in the degradation of methylene blue solution. It is obvious that? TiO2/Ti composite films have antibacterial activity under UV irradiation.展开更多
Nano sized powders of TiO2 （titanium dioxide） and Nb2O5 （Niobium （V） oxide） were used to fabricate TiO2/Nb2O5 composites thin films by EPD （electrophoretic deposition） technique. The metal oxide powders, toget...Nano sized powders of TiO2 （titanium dioxide） and Nb2O5 （Niobium （V） oxide） were used to fabricate TiO2/Nb2O5 composites thin films by EPD （electrophoretic deposition） technique. The metal oxide powders, together with magnesium nitrate hexahydrate pellets, were suspended in propan-2-ol inside an EPD cell. The electrodes, placed 1.2 cm apart, were partially immersed in the suspension and a DC potential applied across them. Key EPD process parameters, which include applied DC electric field, deposition time and solid concentration in suspension, were optimized through visual inspection and from UV-Vis-NIR spectrophotometer spectra. The highest （55%） transmittance was obtained for films with deposition time of 90 s, powder concentration of 0.01 g/40 mL, and 35 V DC （direct current） voltage. XRD micrographs confirmed that TiO2 and Nb2O5 particles were presented in the composite film. SEM （scanning electron microscope） micrographs of the composite electrode thin films showed that porous films of high quality with well controlled morphology were deposited by using the EPD technique.展开更多
Titanium dioxide （TiO2） loaded tungsten trioxide （WO3） composite films are prepared by an E-beam vapor system. Associated with the existence of a heterojunction at the interface of TiO2 and WO3, the prepared TiO2-...Titanium dioxide （TiO2） loaded tungsten trioxide （WO3） composite films are prepared by an E-beam vapor system. Associated with the existence of a heterojunction at the interface of TiO2 and WO3, the prepared TiO2-WO3 composite film shows enhanced photocurrent density, four times than the pure WO3 film illuminated under xenon lamp, and higher incident-photon-to-current conversion e^ciency. By varying the initial TiO2 film thickness, such composite structures could be optimized to obtain the highest photocurrent density. We believe that thin TiO2 films improve the light response and increase the surface roughness of WO3 films. Furthermore, the existence of the heterojunction results in the e^cient charge carriers＇ separation, transfer process, and a lower recombination of electron-hole pairs, which is beneficial for the enhancement of photocurrent density.展开更多
The uniform transparent TiO2/SiO2 photocatalytic composite thin films are prepared by sol-gel method on the soda lime glass substrates, and characterized by UV-visible spectroscopy, X-ray diffraction (XRD), transmissi...The uniform transparent TiO2/SiO2 photocatalytic composite thin films are prepared by sol-gel method on the soda lime glass substrates, and characterized by UV-visible spectroscopy, X-ray diffraction (XRD), transmission electron microscopy (TEM), BET surface area, FTIR spectroscopy and X-ray photoelectron spectroscopy (XPS). It was found that the addition of SiO2 to TiO2 thin films can suppress the grain growth of TiO2 crystal, increase the hydroxyl content on the surface of TiO2 films, lower the contact angle for water on TiO, films and enhance the hydrophilic property of TiO2 films. The super-hydrophilic TiO2/SiO2 photocatalytic composite thin films with the contact angle of 0((o) under bar) are obtained by the addition of 10%-20% SiO2 in mole fraction.展开更多
In this work, a three-layer TiO2 composite film consisting of flower-like TiO2 （Flo-TiO2） as overlayer, TiOa nanotube arrays as interlayer and TiO2 nanoparticle （P25） as underlayer was fabricated as the photoelect...In this work, a three-layer TiO2 composite film consisting of flower-like TiO2 （Flo-TiO2） as overlayer, TiOa nanotube arrays as interlayer and TiO2 nanoparticle （P25） as underlayer was fabricated as the photoelectrode of dyesensitized solar cells （DSSCs）. Due to the introduction of Flo-TiO2, the three-layer composite film has strong lightscattering ability. Then, we have investigated and compared the photoelectric conversion properties of DSSCs based on three-layer structure （P25/TNT arrays/Flo-TiO2） photoelectrode and double-layer film （P25/TNT arrays） photoelectrode. It is found that DSSCs based on three-layer structure exhibit a high power conversion efficiency of 6.48% compared with the DSSCs composed of double-layer film （5.11%）.展开更多
Particulate composites based on isotactic polypropylene(iPP) and titanium dioxide(TiO 2) have been prepared and their morphology and thermal behavior investigated by scanning electron microscopy(SEM), differential sca...Particulate composites based on isotactic polypropylene(iPP) and titanium dioxide(TiO 2) have been prepared and their morphology and thermal behavior investigated by scanning electron microscopy(SEM), differential scanning calorimetry(DSC) and thermogravimetric analysis(TGA). Tensile tests were performed to assess the influence of TiO 2 on the mechanical properties of the iPP.展开更多
Photocatalyst CoPcS/TiO2 was prepared by sol-gel method. Composite CoPcS/TiO2/K2Ti4O9 was prepared by dipping. It was incandesced at various temperatures and modification effect was compared. The results showed that o...Photocatalyst CoPcS/TiO2 was prepared by sol-gel method. Composite CoPcS/TiO2/K2Ti4O9 was prepared by dipping. It was incandesced at various temperatures and modification effect was compared. The results showed that optical absorption of sample incandesce at 423K occurred significant red-shift. Light absorption width extended from ultraviolet region to visible region, especially there was an intensive absorption between 600 nm and 680 nm. X-ray diffraction spectrogram showed that TiO2 in sample still maintained anatase crystal form. Under the illumination of visible light, photocatalysis degradation experiment was taken with Eosin B as simulated pollutants. Decoloration rate of Eosin B was much improved. The rate can reach 80% in 300 minutes.展开更多
With rapid progressive application of TiO2 thin films, magnetron sputtering becomes a very interesting method to prepare such multi-functional thin films. This paper focuses on influences of various deposition process...With rapid progressive application of TiO2 thin films, magnetron sputtering becomes a very interesting method to prepare such multi-functional thin films. This paper focuses on influences of various deposition processes and deposition rate on the structures and properties of TiO2 thin films. Anatase, rutile or amorphous TiO2 films with various crystalline structures and different photocatalytic, optical and electrical properties can be produced by varying sputtering gases, substrate temperature, annealing process, deposition rate and the characteristics of magnetron sputtering. This may in turn affect the functions of TiO2 films in many applications. Furthermore, TiO2-based composites films can overcome many limitations and improve the properties of TiO2 films.展开更多
A new technique for preparing TiO2 modified film on carbon steel was accomplished by electroless plating and sol-gel composite process. The artificial neural network was applied to optimize the preparing condition of ...A new technique for preparing TiO2 modified film on carbon steel was accomplished by electroless plating and sol-gel composite process. The artificial neural network was applied to optimize the preparing condition of TiO2 modified film. The optimized condition for forming TiO2 modified film on carbon steel was that NiP plating for 50 min, dip-coating times as 4, heat treatment time for 2 h, and the molar ratio of complexing agent and Ti(OC4HZ9)4 kept 1.5:1. The results showed that TiO2 modified film have good corrosion resistance. The result conformed that it is feasible to design the preparing conditions of TiO2 modified film by artificial neural network.展开更多
A new TiO2 modified film on carbon steel was prepared by electroless plating and sol gel composite process. An artificial neural net was used to optimize the preparing condition of the film. The optimized condition of...A new TiO2 modified film on carbon steel was prepared by electroless plating and sol gel composite process. An artificial neural net was used to optimize the preparing condition of the film. The optimized condition of the TiO2-modified film on carbon steel is as follows： plating time of NiP is 50 min, number of dip coating is 4, heat treatment time is 2 h, and the molar ratio of complexing reagent to Ti（OC4 H9）4 is 1.5 ： 1. Corrosion behavior of carbon steel with coating was investigated by polarization resistance measurement, anode polarization, EIS and ESEM measurement. XPS was used to characterize the element valence of the modified film. Results show that carbon steel with TiO2 modified film has good corrosion resistance in 0.5 mol/L of H2SO4 solution and 0.5 mol/L of NaCl solution. It is also found that the preparing condition of forming TiO2-modified film can be obtained easily by the artificial neural net.展开更多
In order to clarify the respective role of the UV light, catalyst, external bias as well as their combined effects on the photodegradation process and to clarify the photocatalytic mechanism under different experiment...In order to clarify the respective role of the UV light, catalyst, external bias as well as their combined effects on the photodegradation process and to clarify the photocatalytic mechanism under different experimental conditions, a series of experiments were conducted in a shallow pond photoreactor with an effective volume of 100 mL using TiO 2/Ti thin film prepared by anodization as photocatalyst. A 300W UV lamp( E max =365 nm)was used as side light source. The effect of light intensity on photocatalysis was also conducted. The results show that photocatalytic oxidation is an effective method for phenol removal from waters. The degradation rate can be improved by applying an anodic bias to the TiO 2/Ti film electrode, phenol can not be decomposed under only 365 nm UV light irradiation even in the presence of hydrogen peroxide. In the range of our research, the phenol removal rate can be described in terms of pseudo first order kinetics.展开更多
Al2O3 ceramic powder was applied to modify the large pores defects on the surface of the porous metal Ti support,in situ oxidation method was a convenient method to prepare defect free ceramic/Ti composite membranes o...Al2O3 ceramic powder was applied to modify the large pores defects on the surface of the porous metal Ti support,in situ oxidation method was a convenient method to prepare defect free ceramic/Ti composite membranes on this basis.In situ oxidation conditions experimental results show that the best condition for preparing the TiO2-Al2O3/Ti composite membrane is under 800°C for 2 h,and the microstructure and pore sizes of the TiO2-Al2O3/Ti composite membranes are affected obviously.The thickness and composition of the TiO2/Ti composite membranes are determined by SEM and XRD completely.The pore size distribution of the composite membrane is measured by bubble pressure method,the most probable aperture is about 3.12μm,while the average pore size of defect free TiO2-Al2O3/Ti is about 3.23μm.After ultrasonic treatment,the slight weight change of membranes reveals no observable change,which indicates that TiO2-Al2O3/Ti composite membranes maintain a good stability.展开更多
The crystalline structure and surface morphology of TiO2 semiconductor coating play an important role in the conversion efficiency of dye-sensitized solar cells. In order to obtain TiO2 coating with controllable morph...The crystalline structure and surface morphology of TiO2 semiconductor coating play an important role in the conversion efficiency of dye-sensitized solar cells. In order to obtain TiO2 coating with controllable morphology and high porosity, nanoporous TiO2 films were fabricated on conducting glass （FTO） substrates, Ti thin films （1.5-2 gin） were deposited on conducting glass （FTO） substrates via the DC sputtering method, and then electrochemically anodized in NH4F/ethylene glycol solution. The crystalline structure and surface morphology of the samples were characterized by X-ray diffraction （XRD） and field emission scanning electron microscopy （FESEM）, respectively. The influences of anodizing potential, electrolyte composition, and pH value on the surface morphology of nanoporous TiO2 films were extensively studied. The growth mechanism of nanoporous TiO2 films was discussed by current density variations with anodizing time. The results demonstrate that nanoporous TiO2 films with high porosity and three-dimensional （3D） networks are observed at 30 V, when the NH4F concentration in ethylene glycol solution is 0.3% （mass fraction） and the electrolyte pH value is 5.0.展开更多
基金Project(gf200901002)supported by the Open Research Fund of National Defense Key Disciplines Laboratory of Light Alloy Processing Science and Technology of Nanchang Hangkong University,China
文摘ZrO2/TiO2 composite photocatalytic film was produced on the pure titanium substrate using in-situ Zr（OH）4 colloidal particle by the micro-arc oxidation technique and characterized by scanning electron microscope （SEM）, energy dispersive X-ray （EDX）, X-ray diffraction （XRD） and ultraviolet-visible （UV-Vis） spectrophotometer. The composite film shows a lamellar and porous structure which consists of anatase, futile and ZrO2 phases. The optical absorption edge of film is shifted to longer wavelength when ZrO2 is introduced to TiO2. Furthermore, the photocatalytic reaction rate constants of degradation of rhodamine B solution with ZrO2/TiO2 composite film and pure TiO2 film under ultraviolet irradiation are measured as 0.0442 and 0.0186 h 1, respectively.
基金Project (2010JQ6008) supported by the Natural Science Foundation of Shaanxi Province,China
文摘Series of TiO 2-ZnO heterojunction composite films with different n（Zn）/n（Ti） ratios were prepared by UDP450 magnetron sputter ion plating equipment, and the mole ratio of Zn to Ti was controlled by adjusting the current values of sputtering target. The effects of n（Zn）/n（Ti） on the microstructures of TiO2-ZnO films were investigated by SEM, AFM, Raman and XPS, and their photocatalytic decomposition of methyl orange solutions was evaluated. The results show that an increase in n（Zn）/n（Ti） typically results in a decrease in the grain size of composite films firstly and then an increase of grain size, while an increase in n（Zn）/n（Ti） leads to an increase in film roughness firstly and then a decrease in film roughness. Both grain size and roughness of TiO2-ZnO films reach the maximum and minimum at n（Zn）/n（Ti） of 1/9.3, respectively. The n（Zn）/n（Ti） shows little effect on the valences of Zn and Ti elements, which mainly exist in the form of TiO2 and ZnO phases. The n（Zn）/n（Ti） has influence on the amount of anatase/rutile TiO2 heterojunction in the film. With increase of the n（Zn）/n（Ti）, the absorption intensity of the composite film increases and the absorption region extends to 450 nm, which is redshifted as much as 150 nm in comparison with the pure TiO2 films. However, the photocatalytic abilities of heterogeneous composite films do not depend on the n（Zn）/n（Ti） but rather on the microstructures of the TiO2-ZnO composite films. Degradation rate of the film reaches the maximum and the photocatalytic decomposition of pollutants works best when n（Zn）/n（Ti）=1：9.3.
基金Sponsored by Hi-Tech Research and Development Program of China (2003AA305120)
文摘The Ni-P/TiO2 composite film on sintered NdFeB permanent magnet was investigated by X-ray diffraction （XRD）,environmental scanning electron microscopy （ESEM）,and energy dispersive X-ray spectrometer （EDX）. The corrosion resistance of Ni-P/TiO2 film coated on NdFeB magnet,in 0.5 mol/L NaCl solution,was studied by potentiodynamic polarization,salt spray test and electrochemical impedance spectroscopy （EIS） techniques. The self-corrosion current density （icorr） and the polarization resistance （Rp） of Ni-P/TiO2 film are 0.22 μA/cm2 （about 14% of that of Ni-P coating）,and 120 kΩ·cm2 （about 2 times of that of Ni-P coating）,respectively. The anti-salt spray time of Ni-P/TiO2 film is about 2.5 times of that of the Ni-P coating. The results indicate that Ni-P/TiO2 film has a better corrosion resistance than Ni-P coating,and the composite film increases the corrosion resistance of NdFeB magnet markedly.
基金financially supported by the National Natural Science Foundation of China (No.51301118)the Projects of International Cooperation in Shanxi (No.2014081002)the Scientific and Technological Innovation Programs of Higher Education Institutions in Shanxi (No.2013108)
文摘Cu2O/TiOa/Pt three-layer films were deposited on glass substrates using magnetron sputtering method. The surface morphology and the optical properties of the composite film were characterized by X-ray diffraction （XRD）, scanning electron microscopy （SEM）, ultraviolet- visible spectroscopy （UV-Vis） and photoluminescence spectroscopy （PL）. The photocatalytic activity of the samples was evaluated by the photocatalytic degradation of methyl orange （MO） aqueous solution under visible light irradiation. The results indicate that the Cu2O/TiO2/Pt composite films are made up of three layers which are Pt layer, anatase-TiO2 layer and Cu2O layer from bottom to top. The surface of the films is even and composed of regular-shaped spherical particles. The photocatalytic activity of the Cu2O/TiO2/Pt three-layer film is much higher than that of the Cu2O/TiO2 double-layer film. Such enhancement is ascribed to the presence of Pt layer, which further inhibits the photogenerated electron-hole recombination, prolongs the lifetime of the photogenerated carriers, increases the quantum efficiency and hence improves the photocatalytic activity of the film effectively.
文摘A NiP/TiO2 composite film on carbon steel was prepared by electroless plating and sol-gel composite process. An artificial neural network was applied to optimize the prepared condition of the composite film. Corrosion behavior of the NiP/TiO2 composite film was investigated by polarization resistance measurement, anode polarization, ESEM （environmental scanning electron microscopy） and EIS （electrochemical impedance spectroscopy） measurements. Results showed that the NiP/ TiO2 composite film has a good corrosion resistance in 0.5mol/L H2SO4 solution. The element valence of the composite film was characterized by XPS （X-ray photoelectron spectroscopy） spectrum, and an anticorrosion mechanism of the composite film was discussed.
文摘In this work, TiO2/Ti composite films were fabricated by 2-setp MCT and the following high temperature oxidation. Antibacterial activity of the composite films treated by ultrasonic cleaning to increase the performance reliability was examined. The prepared TiO2/Ti composite films showed high photocatalytic activity in the degradation of methylene blue solution. It is obvious that? TiO2/Ti composite films have antibacterial activity under UV irradiation.
文摘Nano sized powders of TiO2 （titanium dioxide） and Nb2O5 （Niobium （V） oxide） were used to fabricate TiO2/Nb2O5 composites thin films by EPD （electrophoretic deposition） technique. The metal oxide powders, together with magnesium nitrate hexahydrate pellets, were suspended in propan-2-ol inside an EPD cell. The electrodes, placed 1.2 cm apart, were partially immersed in the suspension and a DC potential applied across them. Key EPD process parameters, which include applied DC electric field, deposition time and solid concentration in suspension, were optimized through visual inspection and from UV-Vis-NIR spectrophotometer spectra. The highest （55%） transmittance was obtained for films with deposition time of 90 s, powder concentration of 0.01 g/40 mL, and 35 V DC （direct current） voltage. XRD micrographs confirmed that TiO2 and Nb2O5 particles were presented in the composite film. SEM （scanning electron microscope） micrographs of the composite electrode thin films showed that porous films of high quality with well controlled morphology were deposited by using the EPD technique.
基金Supported by the National Natural Science Foundation of China under Grant Nos 11174137,11474215 and 21204058the Natural Science Foundation for the Youth of Jiangsu Province under Grant No BK20130284the Priority Academic Program Development of Jiangsu Higher Education Institutions
文摘Titanium dioxide （TiO2） loaded tungsten trioxide （WO3） composite films are prepared by an E-beam vapor system. Associated with the existence of a heterojunction at the interface of TiO2 and WO3, the prepared TiO2-WO3 composite film shows enhanced photocurrent density, four times than the pure WO3 film illuminated under xenon lamp, and higher incident-photon-to-current conversion e^ciency. By varying the initial TiO2 film thickness, such composite structures could be optimized to obtain the highest photocurrent density. We believe that thin TiO2 films improve the light response and increase the surface roughness of WO3 films. Furthermore, the existence of the heterojunction results in the e^cient charge carriers＇ separation, transfer process, and a lower recombination of electron-hole pairs, which is beneficial for the enhancement of photocurrent density.
基金This work was financially supported by the Foundation for University Key Teachers by the Ministry of Education, theKey Resear
文摘The uniform transparent TiO2/SiO2 photocatalytic composite thin films are prepared by sol-gel method on the soda lime glass substrates, and characterized by UV-visible spectroscopy, X-ray diffraction (XRD), transmission electron microscopy (TEM), BET surface area, FTIR spectroscopy and X-ray photoelectron spectroscopy (XPS). It was found that the addition of SiO2 to TiO2 thin films can suppress the grain growth of TiO2 crystal, increase the hydroxyl content on the surface of TiO2 films, lower the contact angle for water on TiO, films and enhance the hydrophilic property of TiO2 films. The super-hydrophilic TiO2/SiO2 photocatalytic composite thin films with the contact angle of 0((o) under bar) are obtained by the addition of 10%-20% SiO2 in mole fraction.
基金supported by the National Natural Science Foundation of China (Nos. 51572072 and 11204070)the Fundamental Research Funds for the Central Universities (No. 2014-Ia-028)financially supported by State Key Laboratory of Advanced Technology for Materials Synthesis and Processing (No. 2016-KF-13)
文摘In this work, a three-layer TiO2 composite film consisting of flower-like TiO2 （Flo-TiO2） as overlayer, TiOa nanotube arrays as interlayer and TiO2 nanoparticle （P25） as underlayer was fabricated as the photoelectrode of dyesensitized solar cells （DSSCs）. Due to the introduction of Flo-TiO2, the three-layer composite film has strong lightscattering ability. Then, we have investigated and compared the photoelectric conversion properties of DSSCs based on three-layer structure （P25/TNT arrays/Flo-TiO2） photoelectrode and double-layer film （P25/TNT arrays） photoelectrode. It is found that DSSCs based on three-layer structure exhibit a high power conversion efficiency of 6.48% compared with the DSSCs composed of double-layer film （5.11%）.
文摘Particulate composites based on isotactic polypropylene(iPP) and titanium dioxide(TiO 2) have been prepared and their morphology and thermal behavior investigated by scanning electron microscopy(SEM), differential scanning calorimetry(DSC) and thermogravimetric analysis(TGA). Tensile tests were performed to assess the influence of TiO 2 on the mechanical properties of the iPP.
基金Acknowledgements： This project is supported by the fund of the Plan of Postgraduate Scientific Research Innovation of Jiangsu Province （No. CX07B_175z） and the Natural Science Foundation of Henan Province （No. 0624720029）.
文摘Photocatalyst CoPcS/TiO2 was prepared by sol-gel method. Composite CoPcS/TiO2/K2Ti4O9 was prepared by dipping. It was incandesced at various temperatures and modification effect was compared. The results showed that optical absorption of sample incandesce at 423K occurred significant red-shift. Light absorption width extended from ultraviolet region to visible region, especially there was an intensive absorption between 600 nm and 680 nm. X-ray diffraction spectrogram showed that TiO2 in sample still maintained anatase crystal form. Under the illumination of visible light, photocatalysis degradation experiment was taken with Eosin B as simulated pollutants. Decoloration rate of Eosin B was much improved. The rate can reach 80% in 300 minutes.
文摘With rapid progressive application of TiO2 thin films, magnetron sputtering becomes a very interesting method to prepare such multi-functional thin films. This paper focuses on influences of various deposition processes and deposition rate on the structures and properties of TiO2 thin films. Anatase, rutile or amorphous TiO2 films with various crystalline structures and different photocatalytic, optical and electrical properties can be produced by varying sputtering gases, substrate temperature, annealing process, deposition rate and the characteristics of magnetron sputtering. This may in turn affect the functions of TiO2 films in many applications. Furthermore, TiO2-based composites films can overcome many limitations and improve the properties of TiO2 films.
文摘A new technique for preparing TiO2 modified film on carbon steel was accomplished by electroless plating and sol-gel composite process. The artificial neural network was applied to optimize the preparing condition of TiO2 modified film. The optimized condition for forming TiO2 modified film on carbon steel was that NiP plating for 50 min, dip-coating times as 4, heat treatment time for 2 h, and the molar ratio of complexing agent and Ti(OC4HZ9)4 kept 1.5:1. The results showed that TiO2 modified film have good corrosion resistance. The result conformed that it is feasible to design the preparing conditions of TiO2 modified film by artificial neural network.
文摘A new TiO2 modified film on carbon steel was prepared by electroless plating and sol gel composite process. An artificial neural net was used to optimize the preparing condition of the film. The optimized condition of the TiO2-modified film on carbon steel is as follows： plating time of NiP is 50 min, number of dip coating is 4, heat treatment time is 2 h, and the molar ratio of complexing reagent to Ti（OC4 H9）4 is 1.5 ： 1. Corrosion behavior of carbon steel with coating was investigated by polarization resistance measurement, anode polarization, EIS and ESEM measurement. XPS was used to characterize the element valence of the modified film. Results show that carbon steel with TiO2 modified film has good corrosion resistance in 0.5 mol/L of H2SO4 solution and 0.5 mol/L of NaCl solution. It is also found that the preparing condition of forming TiO2-modified film can be obtained easily by the artificial neural net.
文摘In order to clarify the respective role of the UV light, catalyst, external bias as well as their combined effects on the photodegradation process and to clarify the photocatalytic mechanism under different experimental conditions, a series of experiments were conducted in a shallow pond photoreactor with an effective volume of 100 mL using TiO 2/Ti thin film prepared by anodization as photocatalyst. A 300W UV lamp( E max =365 nm)was used as side light source. The effect of light intensity on photocatalysis was also conducted. The results show that photocatalytic oxidation is an effective method for phenol removal from waters. The degradation rate can be improved by applying an anodic bias to the TiO 2/Ti film electrode, phenol can not be decomposed under only 365 nm UV light irradiation even in the presence of hydrogen peroxide. In the range of our research, the phenol removal rate can be described in terms of pseudo first order kinetics.
基金Projects(212006065,21666018)supported by the National Natural Science Foundation of China
文摘Al2O3 ceramic powder was applied to modify the large pores defects on the surface of the porous metal Ti support,in situ oxidation method was a convenient method to prepare defect free ceramic/Ti composite membranes on this basis.In situ oxidation conditions experimental results show that the best condition for preparing the TiO2-Al2O3/Ti composite membrane is under 800°C for 2 h,and the microstructure and pore sizes of the TiO2-Al2O3/Ti composite membranes are affected obviously.The thickness and composition of the TiO2/Ti composite membranes are determined by SEM and XRD completely.The pore size distribution of the composite membrane is measured by bubble pressure method,the most probable aperture is about 3.12μm,while the average pore size of defect free TiO2-Al2O3/Ti is about 3.23μm.After ultrasonic treatment,the slight weight change of membranes reveals no observable change,which indicates that TiO2-Al2O3/Ti composite membranes maintain a good stability.
基金Projects(21171027,50872014) supported by the National Natural Science Foundation of ChinaProject(K1001020-11)supported by the Science and Technology Key Project of Changsha City,China
文摘The crystalline structure and surface morphology of TiO2 semiconductor coating play an important role in the conversion efficiency of dye-sensitized solar cells. In order to obtain TiO2 coating with controllable morphology and high porosity, nanoporous TiO2 films were fabricated on conducting glass （FTO） substrates, Ti thin films （1.5-2 gin） were deposited on conducting glass （FTO） substrates via the DC sputtering method, and then electrochemically anodized in NH4F/ethylene glycol solution. The crystalline structure and surface morphology of the samples were characterized by X-ray diffraction （XRD） and field emission scanning electron microscopy （FESEM）, respectively. The influences of anodizing potential, electrolyte composition, and pH value on the surface morphology of nanoporous TiO2 films were extensively studied. The growth mechanism of nanoporous TiO2 films was discussed by current density variations with anodizing time. The results demonstrate that nanoporous TiO2 films with high porosity and three-dimensional （3D） networks are observed at 30 V, when the NH4F concentration in ethylene glycol solution is 0.3% （mass fraction） and the electrolyte pH value is 5.0.
