A novel soft polymer template containing a double-layer structure,which includes a thin layer of polymethylmethacrylate(PMMA)used as a pattern layer and a thicker layer of polydimethylsiloxane(PDMS)used as a back laye...A novel soft polymer template containing a double-layer structure,which includes a thin layer of polymethylmethacrylate(PMMA)used as a pattern layer and a thicker layer of polydimethylsiloxane(PDMS)used as a back layer,was fabricated from a replica molding process.Anodic aluminum oxide(AAO)template was used as the replica mold to be replicated to the polymethylmethacrylate layer by a thermal infiltration process under a vacuum condition.Results indicate that PMMA/PDMS soft templates with different sizes could be easily fabricated from the as-prepared AAO replica mold.The PMMA/PDMS soft templates were then employed to imprint a TiO_2 gel for achieving TiO_2 nano-pore arrays.After the imprinting process,the PDMS layer was firstly peeled off and the PMMA layer was then removed into acetonitrile,which can avoid any demolding problems like damages or distortions.The TiO_2 nano-pore arrays with the crystalline of anatase could be obtained at a heat treatment temperature of 450°C.展开更多
Well crystallized niobium-doped TiO; nanotube arrays （TiNbO-NT） were successfully synthesized via the anodization of titanium/niobium alloy sheets, followed with a heat treatment at 550 ℃ for 2 h. Morphology analys...Well crystallized niobium-doped TiO; nanotube arrays （TiNbO-NT） were successfully synthesized via the anodization of titanium/niobium alloy sheets, followed with a heat treatment at 550 ℃ for 2 h. Morphology analysis results demonstrated that both the titanium/niobium alloy microstructure and the dissolution strength of electrolyte played major roles in the formation of nanotube structure. A single-phase microstructure was more favorable to the formation of uniform nanotube arrays, while modulating the dissolution strength of electrolyte was required to obtain nanotube arrays from the alloys with multi-phase microstructures. X-ray diffraction （XRD） and X-ray photoelectron （XPS） analysis results clearly demonstrated that niobium dopants （Nb^5＋） were successfully doped into TiO2 anatase lattice by substituting Ti^4＋ in this approach.展开更多
Vertically aligned TiO2/SrTiO3 core–shell heterostructured nanowire arrays with different shell thicknesses(5–40 nm)were fabricated on fluorine-doped tin oxide substrate via a hydrothermal process.Microstructural ch...Vertically aligned TiO2/SrTiO3 core–shell heterostructured nanowire arrays with different shell thicknesses(5–40 nm)were fabricated on fluorine-doped tin oxide substrate via a hydrothermal process.Microstructural characterization demonstrated that the TiO2 nanowires were uniformly coated by the singlecrystal SrTiO3 shell,where continuous and large-area interface could be clearly observed.By this means,significantly enhanced photoelectrochemical water splitting properties(0.78 mA·cm^-2 at 1.23 V vs.RHE)were successfully realized in well-designed sample(with a shell thickness of 5–10 nm)compared with those of pristine TiO2(0.38 mA·cm^-2 at 1.23 V vs.RHE).The improvement of photoelectrochemical properties was attributed to the improved charge injection and charge separation,which are calculated by the results of water oxidation and sulfite oxidation measurements.Based on these results,a mechanism was proposed that SrTiO3 shell acted as an electron–hole separation layer to improve the photocurrent density.On the other hand,the sample with an over-thick SrTiO3 shell(20–40 nm)exhibited slightly reduced photoelectrochemical properties(0.66 mA·cm^-2),which could be explained by the increase of the recombination rate in thethicker SrTiO3 shell.This work provided a facile strategy to improve and modulate the photoelectrochemical performance of heterostructured photoanodes.展开更多
TiO2 nanotube （TNT） arrays were fabricated by anodic oxidation of titanium foil in a fluoride- based solution, on which Cu20 particles were loaded via galvanostatic pulse electrodeposition in cupric acetate solution...TiO2 nanotube （TNT） arrays were fabricated by anodic oxidation of titanium foil in a fluoride- based solution, on which Cu20 particles were loaded via galvanostatic pulse electrodeposition in cupric acetate solutions in the absence of any other additives. The structure and optical properties of Cu2O-loaded TiO2 nanotube arrays （Cu2O-TNTs） were analyzed by scanning electron microscopy （SEM）, X-ray diffraction （XRD） and UV-Vis absorption, and the photoelectrochemical performance was measured using an electrochemical work station with a three-electrode configuration. The results show that the Cu2O particles distribute uniformly on the highly ordered anatase TiO2 nanotube arrays. The morphologies of Cu2O crystals change from branched, truncated octahedrons to dispersive single octahedrons with increasing deposition current densities. The Cu2O- TNTs exhibited remarkable visible light responses with obvious visible light absorption and greatly enhanced visible light photoelectrochemical performance. The I-V characteristics under visible light irradiation show a distinct plateau in the region between approximately -0.3 and 0 V, resulting in higher open-circuit voltages and larger short-circuit currents with increased Cu2O deposition.展开更多
TiO_(2) nanotube arrays,growing on three-dimensional(3 D)porous Ti membrane,were synthesized using a facile nonsolvent-induced phase separation and anodization process.The length of those three-dimensional nanotube ar...TiO_(2) nanotube arrays,growing on three-dimensional(3 D)porous Ti membrane,were synthesized using a facile nonsolvent-induced phase separation and anodization process.The length of those three-dimensional nanotube arrays could be tuned by prolonging the anodizing time.When the anodizing time is 8 h,the three-dimensional TiO_(2) nanotube arrays/porous Ti electrode exhibits well cycling stability and ultra-high specific capacity,which is used in lithium-ion batteries,attributed to the high utilization rate of the substrate and the high growth intensity of the active materials.Three-dimensional TiO_(2) nano tube arrays/porous Ti electrode,at 100μA·cm^(-2) with 8 h anodizing time,shows a typical discharge plateau at 1.78 V and exhibits the specific capacity with 2126.7μAh·cm^(-2),The novel nanotube arrays@3 D porous architecture effectively shortens the electron/ion transmission path,which could pave way for optimizing the design of highperformance anode materials for next-generation energy storage system.展开更多
The highly ordered TiO2 nanotubes (NTs) were fabricated by the anodic oxidation method. Their morphology, structure and crystalline phase were characterized by scanning electron microscopy (SEM) and X-ray diffractomet...The highly ordered TiO2 nanotubes (NTs) were fabricated by the anodic oxidation method. Their morphology, structure and crystalline phase were characterized by scanning electron microscopy (SEM) and X-ray diffractometer (XRD). The effects of morphology, specific surface area, pore structures and photo catalytic activity of the TiO2 NTs were investigated. UV-vis spectra analysis showed that its light absorption had been extended to the visible light range. The photocatalytic activity of the as-prepared samples was evaluated by photocatalytic oxidation of gaseous HCHO and MB aqueous solution. The samples had better adhesion strength in the dark and showed a higher photocatalytic activity than nanoparticles. Especially, with ultraviolet light pretreatment, the nanotubes exhibited more stable active for photocatalytic decomposition and the photodecomposition rate remained at high level after 3 cycles of the photocatalysis experiment. Thus, how the number of surface active group center dot OH increased and the mechanism for the great improvement for the photocatalytic activity are discussed. (C) 2016 Science Press and Dalian Institute of Chemical Physics, Chinese Academy of Sciences. Published by Elsevier B.V. and Science Press. All rights reserved.展开更多
Au nanoparticle-decorated TiO2 nanotube arrays are prepared by a simple method, which is a thermal annealing thin gold film deposited on anodie oxidized TiO2 nanotube arrays. These electron microscope images present t...Au nanoparticle-decorated TiO2 nanotube arrays are prepared by a simple method, which is a thermal annealing thin gold film deposited on anodie oxidized TiO2 nanotube arrays. These electron microscope images present that Au nanoparticles are well dispersed within the wall and on the surface of the XiO2 nanotubes. Meanwhile, the morphologies of Au nanoparticles can be controlled by changing the thickness of the deposited gold film. Associ- ated with the excitation of localized surface plasmon resonances, the prepared Au nanoparticle-decorated TiO2 nanotube arrays could work as visible light responsive photocatalysts to produce a greatly enhanced photocurrent density. By varying the initial gold film thickness, such Au nanoparticle-decorated TiO2 nanotube arrays could be optimized to obtain the highest photocurrent generation efficiency in the visible and UV light regions.展开更多
Highly ordered TiO_2 nanotube arrays(NTAs) on Si substrate possess broad applications due to its high surfaceto-volume ratio and novel functionalities, however, there are still some challenges on facile synthesis. Her...Highly ordered TiO_2 nanotube arrays(NTAs) on Si substrate possess broad applications due to its high surfaceto-volume ratio and novel functionalities, however, there are still some challenges on facile synthesis. Here, we report a simple and cost-effective high-field(90–180V) anodization method to grow highly ordered TiO_2 NTAs on Si substrate,and investigate the effect of anodization time, voltage, and fluoride content on the formation of TiO_2 NTAs. The current density–time curves, recorded during anodization processes, can be used to determine the optimum anodization time. It is found that the growth rate of TiO_2 NTAs is improved significantly under high field, which is nearly 8 times faster than that under low fields(40–60 V). The length and growth rate of the nanotubes are further increased with the increase of fluoride content in the electrolyte.展开更多
Titania nanotubular arrays （TNA） synthesized via electrochemical anodization is a stable and versatile material, widely studied for photocatalytic and sensing applications, whereas nano-sized gold particles are a kn...Titania nanotubular arrays （TNA） synthesized via electrochemical anodization is a stable and versatile material, widely studied for photocatalytic and sensing applications, whereas nano-sized gold particles are a known plasmonic material. Semiconductor-metal nanocomposites in isolated, embedded, or encapsulated form, when irradiated with proper light frequency can exhibit localized surface plasmon resonance （LSPR） effect. This effect can result in improved light adsorption and electrical properties of a material. In this study, we report the enhanced visible light photo-response of LSPR induced volatile organic biomarker vapor sensing at room temperature using a Au-embedded TNA electrochemical sensor. Two mechanisms are proposed. One based on classical physics （band theory）, which explains operation under non-irradiated conditions. The second mechanism is based on the coupling of classical and quantum physics （molecular orbitals）, and explains sensor operation under irradiated conditions.展开更多
CdS quantum dots（QDs） sensitized TiO2 nanotube arrays photoelectrodes were investigated for their photovoltaic performance of quantum dots-sensitized solar cells. The highly ordered TiO2 nanotube arrays（TNAs） were...CdS quantum dots（QDs） sensitized TiO2 nanotube arrays photoelectrodes were investigated for their photovoltaic performance of quantum dots-sensitized solar cells. The highly ordered TiO2 nanotube arrays（TNAs） were synthesized on Ti foils by anodic oxidation method. Then CdS quantum dots were deposited onto the TiO2 nanotube arrays by successive ionic layer absorption and reaction（SILAR） method to serve as the sensitizers. Cd（NO3）2 and Na2S were used as the precursor materials of Cd＋ and S2- ions, respectively. It is found that the CdS QDs sensitizer may significantly increase the light response of TiO2 nanotube arrays. With increasing CdS QDs deposition cycles, the visible light response increases. Maximum photocurrent was obtained for the QDs that have an absorption peak at about 500 nm. Under AM 1.5 G illuminations（100 mW cm^-2）, a 4.85 mA/cm^2 short circuit current density was achieved, and the maximium energy conversion efficiency of the asprepared CdS QDs-sensitized TNAs solar cells was obtained as high as 0.81% at five SILAR cycles.展开更多
TiO2 films have been widely applied in photo- voltaic conversion techniques. TiO2 nanotube arrays （TiO2 NAs） can be grown directly on the surface of metal Ti by the anodic oxidation method. Bi2S3 and PbS nanoparticl...TiO2 films have been widely applied in photo- voltaic conversion techniques. TiO2 nanotube arrays （TiO2 NAs） can be grown directly on the surface of metal Ti by the anodic oxidation method. Bi2S3 and PbS nanoparticles （NPs） were firstly co-sensitized on TiOa NAs （denoted as PbS/Bi2S3（n）/TiO2 NAs） by a two-step process containing hydrothermal and sonication-assisted SILAR method. When the concentration of Bi3＋ is 5 mmol/L, the best photoelectrical performance was obtained under simulated solar irradiation. The short-circuit photocurrent （Jsc） and photoconversion efficiency （η） of PbS/Bi2S3（5）/TiO2 NAs electrode were 4.70 mA/cm and 1.13 %, respectively.展开更多
TiO2 nanowire arrays were successfully fabricated by liquid-phase deposition method using porous alumina templates. The obtained TiO2 nanowires were characterized using Raman spectroscopy, X-ray diffraction （XRD）, s...TiO2 nanowire arrays were successfully fabricated by liquid-phase deposition method using porous alumina templates. The obtained TiO2 nanowires were characterized using Raman spectroscopy, X-ray diffraction （XRD）, scanning electron microscopy （SEM）, field emission scanning electron microscopy （FE- SEM）, transmission electron microscopy （TEM）, and selected area electron diffraction （SAED） analysis. Results of electron microscopic observations indicated that the nanowires were smooth and uniform with a diameter of about 50-80 nm and several micrometers in length. SAED, Raman, and XRD mea- surements showed that TiO2 nanowires were single-crystalline with a pure rutile structure after heating at 800 ~C for 10 h. In this situation, the nanowire constituents grew preferentially along the 〈001〉 direction. Furthermore, the formation process and mechanistic study of the Ti02 nanowire arrays were proposed and discussed in detail. The nanowires are clearly produced by the deposition of TiO2 particles on the inner wall of the template nanochannels.展开更多
Surface with TiO2 nanotube arrays(TNTAs)is superhydrophilic and of great specific area.This paper investigates the pool boiling characteristics at the thermal interface with TNTAs.The results show that the TNTAs inter...Surface with TiO2 nanotube arrays(TNTAs)is superhydrophilic and of great specific area.This paper investigates the pool boiling characteristics at the thermal interface with TNTAs.The results show that the TNTAs interface can enhance the pool boiling heat transfer compared to the pure Ti metal plate.The bubbles formed at the initial nucleation state are very small and released in higher frequency.The pool boiling heat transfer enhancement at the TNTAs interface may be attributed to the high density of nucleate site,high intrinsic heating area of nanotubes layer,superhydrophilicity and the vertically oriented nanotube structure.展开更多
基金supported by the Ministry of Science and Technology of China through 863-project under grant 2009AA03Z218the Major Program of the National Natural Science Foundation of China under Grant No.90923012the Research Fund for the Doctoral Program of Higher Education of China under grant 200806980023
文摘A novel soft polymer template containing a double-layer structure,which includes a thin layer of polymethylmethacrylate(PMMA)used as a pattern layer and a thicker layer of polydimethylsiloxane(PDMS)used as a back layer,was fabricated from a replica molding process.Anodic aluminum oxide(AAO)template was used as the replica mold to be replicated to the polymethylmethacrylate layer by a thermal infiltration process under a vacuum condition.Results indicate that PMMA/PDMS soft templates with different sizes could be easily fabricated from the as-prepared AAO replica mold.The PMMA/PDMS soft templates were then employed to imprint a TiO_2 gel for achieving TiO_2 nano-pore arrays.After the imprinting process,the PDMS layer was firstly peeled off and the PMMA layer was then removed into acetonitrile,which can avoid any demolding problems like damages or distortions.The TiO_2 nano-pore arrays with the crystalline of anatase could be obtained at a heat treatment temperature of 450°C.
基金supported by the National Natural Science Foundation of China (Grant No. 51102246)the Knowledge Innovation Program of Institute of Metal Research, Chinese Academy of Sciences (Grant No.Y0N5A111A1)the Youth Innovation Promotion Association, Chinese Academy of Sciences (Grant No.Y2N5711171)
文摘Well crystallized niobium-doped TiO; nanotube arrays （TiNbO-NT） were successfully synthesized via the anodization of titanium/niobium alloy sheets, followed with a heat treatment at 550 ℃ for 2 h. Morphology analysis results demonstrated that both the titanium/niobium alloy microstructure and the dissolution strength of electrolyte played major roles in the formation of nanotube structure. A single-phase microstructure was more favorable to the formation of uniform nanotube arrays, while modulating the dissolution strength of electrolyte was required to obtain nanotube arrays from the alloys with multi-phase microstructures. X-ray diffraction （XRD） and X-ray photoelectron （XPS） analysis results clearly demonstrated that niobium dopants （Nb^5＋） were successfully doped into TiO2 anatase lattice by substituting Ti^4＋ in this approach.
基金financially supported by the National Natural Science Foundation of China (Nos. 51232006, 51472218 and 11474249)the National Basic Research Program of China (No. 2015CB654900)
文摘Vertically aligned TiO2/SrTiO3 core–shell heterostructured nanowire arrays with different shell thicknesses(5–40 nm)were fabricated on fluorine-doped tin oxide substrate via a hydrothermal process.Microstructural characterization demonstrated that the TiO2 nanowires were uniformly coated by the singlecrystal SrTiO3 shell,where continuous and large-area interface could be clearly observed.By this means,significantly enhanced photoelectrochemical water splitting properties(0.78 mA·cm^-2 at 1.23 V vs.RHE)were successfully realized in well-designed sample(with a shell thickness of 5–10 nm)compared with those of pristine TiO2(0.38 mA·cm^-2 at 1.23 V vs.RHE).The improvement of photoelectrochemical properties was attributed to the improved charge injection and charge separation,which are calculated by the results of water oxidation and sulfite oxidation measurements.Based on these results,a mechanism was proposed that SrTiO3 shell acted as an electron–hole separation layer to improve the photocurrent density.On the other hand,the sample with an over-thick SrTiO3 shell(20–40 nm)exhibited slightly reduced photoelectrochemical properties(0.66 mA·cm^-2),which could be explained by the increase of the recombination rate in thethicker SrTiO3 shell.This work provided a facile strategy to improve and modulate the photoelectrochemical performance of heterostructured photoanodes.
基金Funded by the National Natural Science Foundation of China(No.51175363)the Youth Staff Fund of Taiyuan University of Technology(Nos.K201016,K201013)+1 种基金the Specialized Fund for Innovative of College Students of Taiyuan City(No.09122018)the Program for Changjiang Scholar and Innovative Research Team in University(No.IRT0972)
文摘TiO2 nanotube （TNT） arrays were fabricated by anodic oxidation of titanium foil in a fluoride- based solution, on which Cu20 particles were loaded via galvanostatic pulse electrodeposition in cupric acetate solutions in the absence of any other additives. The structure and optical properties of Cu2O-loaded TiO2 nanotube arrays （Cu2O-TNTs） were analyzed by scanning electron microscopy （SEM）, X-ray diffraction （XRD） and UV-Vis absorption, and the photoelectrochemical performance was measured using an electrochemical work station with a three-electrode configuration. The results show that the Cu2O particles distribute uniformly on the highly ordered anatase TiO2 nanotube arrays. The morphologies of Cu2O crystals change from branched, truncated octahedrons to dispersive single octahedrons with increasing deposition current densities. The Cu2O- TNTs exhibited remarkable visible light responses with obvious visible light absorption and greatly enhanced visible light photoelectrochemical performance. The I-V characteristics under visible light irradiation show a distinct plateau in the region between approximately -0.3 and 0 V, resulting in higher open-circuit voltages and larger short-circuit currents with increased Cu2O deposition.
基金the National Natural Science Foundation of China(Nos.51801136,51701142 and 51871165)Tianjin Municipal Education Committee Scientific Research Projects(No.2017KJ075)the Australian Research Council Discovery Project(No.DP200100965)。
文摘TiO_(2) nanotube arrays,growing on three-dimensional(3 D)porous Ti membrane,were synthesized using a facile nonsolvent-induced phase separation and anodization process.The length of those three-dimensional nanotube arrays could be tuned by prolonging the anodizing time.When the anodizing time is 8 h,the three-dimensional TiO_(2) nanotube arrays/porous Ti electrode exhibits well cycling stability and ultra-high specific capacity,which is used in lithium-ion batteries,attributed to the high utilization rate of the substrate and the high growth intensity of the active materials.Three-dimensional TiO_(2) nano tube arrays/porous Ti electrode,at 100μA·cm^(-2) with 8 h anodizing time,shows a typical discharge plateau at 1.78 V and exhibits the specific capacity with 2126.7μAh·cm^(-2),The novel nanotube arrays@3 D porous architecture effectively shortens the electron/ion transmission path,which could pave way for optimizing the design of highperformance anode materials for next-generation energy storage system.
基金financial support from Tianjin Science and Technology Support Plan Key Projects(NO.12ZCZDJC35600)
文摘The highly ordered TiO2 nanotubes (NTs) were fabricated by the anodic oxidation method. Their morphology, structure and crystalline phase were characterized by scanning electron microscopy (SEM) and X-ray diffractometer (XRD). The effects of morphology, specific surface area, pore structures and photo catalytic activity of the TiO2 NTs were investigated. UV-vis spectra analysis showed that its light absorption had been extended to the visible light range. The photocatalytic activity of the as-prepared samples was evaluated by photocatalytic oxidation of gaseous HCHO and MB aqueous solution. The samples had better adhesion strength in the dark and showed a higher photocatalytic activity than nanoparticles. Especially, with ultraviolet light pretreatment, the nanotubes exhibited more stable active for photocatalytic decomposition and the photodecomposition rate remained at high level after 3 cycles of the photocatalysis experiment. Thus, how the number of surface active group center dot OH increased and the mechanism for the great improvement for the photocatalytic activity are discussed. (C) 2016 Science Press and Dalian Institute of Chemical Physics, Chinese Academy of Sciences. Published by Elsevier B.V. and Science Press. All rights reserved.
基金Supported by the National Natural Science Foundation of China under Grant Nos 11474215 and 21204058the Priority Academic Program Development of Jiangsu Higher Education Institutions
文摘Au nanoparticle-decorated TiO2 nanotube arrays are prepared by a simple method, which is a thermal annealing thin gold film deposited on anodie oxidized TiO2 nanotube arrays. These electron microscope images present that Au nanoparticles are well dispersed within the wall and on the surface of the XiO2 nanotubes. Meanwhile, the morphologies of Au nanoparticles can be controlled by changing the thickness of the deposited gold film. Associ- ated with the excitation of localized surface plasmon resonances, the prepared Au nanoparticle-decorated TiO2 nanotube arrays could work as visible light responsive photocatalysts to produce a greatly enhanced photocurrent density. By varying the initial gold film thickness, such Au nanoparticle-decorated TiO2 nanotube arrays could be optimized to obtain the highest photocurrent generation efficiency in the visible and UV light regions.
基金supported by National 863 Program 2011AA050518the Natural Science Foundation of China(Grant Nos.11174197,11574203,and 61234005)
文摘Highly ordered TiO_2 nanotube arrays(NTAs) on Si substrate possess broad applications due to its high surfaceto-volume ratio and novel functionalities, however, there are still some challenges on facile synthesis. Here, we report a simple and cost-effective high-field(90–180V) anodization method to grow highly ordered TiO_2 NTAs on Si substrate,and investigate the effect of anodization time, voltage, and fluoride content on the formation of TiO_2 NTAs. The current density–time curves, recorded during anodization processes, can be used to determine the optimum anodization time. It is found that the growth rate of TiO_2 NTAs is improved significantly under high field, which is nearly 8 times faster than that under low fields(40–60 V). The length and growth rate of the nanotubes are further increased with the increase of fluoride content in the electrolyte.
基金supported in part by NSF-STTR Award#IIP-13211530 subcontracted from Nano Synth Materials and Sensors LLC and Utah Government of Economic Development fundsSupport and facilities provided by the Dawn and Roger Crus Renewable Energy Center
文摘Titania nanotubular arrays （TNA） synthesized via electrochemical anodization is a stable and versatile material, widely studied for photocatalytic and sensing applications, whereas nano-sized gold particles are a known plasmonic material. Semiconductor-metal nanocomposites in isolated, embedded, or encapsulated form, when irradiated with proper light frequency can exhibit localized surface plasmon resonance （LSPR） effect. This effect can result in improved light adsorption and electrical properties of a material. In this study, we report the enhanced visible light photo-response of LSPR induced volatile organic biomarker vapor sensing at room temperature using a Au-embedded TNA electrochemical sensor. Two mechanisms are proposed. One based on classical physics （band theory）, which explains operation under non-irradiated conditions. The second mechanism is based on the coupling of classical and quantum physics （molecular orbitals）, and explains sensor operation under irradiated conditions.
基金Funded by Major State Basic Research Development Program of China (973 Program) (No.2009CB939704)Key Project of Chinese Ministry of Education (No.309021)
文摘CdS quantum dots（QDs） sensitized TiO2 nanotube arrays photoelectrodes were investigated for their photovoltaic performance of quantum dots-sensitized solar cells. The highly ordered TiO2 nanotube arrays（TNAs） were synthesized on Ti foils by anodic oxidation method. Then CdS quantum dots were deposited onto the TiO2 nanotube arrays by successive ionic layer absorption and reaction（SILAR） method to serve as the sensitizers. Cd（NO3）2 and Na2S were used as the precursor materials of Cd＋ and S2- ions, respectively. It is found that the CdS QDs sensitizer may significantly increase the light response of TiO2 nanotube arrays. With increasing CdS QDs deposition cycles, the visible light response increases. Maximum photocurrent was obtained for the QDs that have an absorption peak at about 500 nm. Under AM 1.5 G illuminations（100 mW cm^-2）, a 4.85 mA/cm^2 short circuit current density was achieved, and the maximium energy conversion efficiency of the asprepared CdS QDs-sensitized TNAs solar cells was obtained as high as 0.81% at five SILAR cycles.
基金supported by Program of International S&T Cooperation(2013 DFA51050)National Magnetic Confinement Fusion Science Program(2013GB110001)+2 种基金the 863Program(2014AA032701)the National Natural Science Foundation of China(11405138,51302231)the Western Superconducting Technologies Co.,Ltd
文摘TiO2 films have been widely applied in photo- voltaic conversion techniques. TiO2 nanotube arrays （TiO2 NAs） can be grown directly on the surface of metal Ti by the anodic oxidation method. Bi2S3 and PbS nanoparticles （NPs） were firstly co-sensitized on TiOa NAs （denoted as PbS/Bi2S3（n）/TiO2 NAs） by a two-step process containing hydrothermal and sonication-assisted SILAR method. When the concentration of Bi3＋ is 5 mmol/L, the best photoelectrical performance was obtained under simulated solar irradiation. The short-circuit photocurrent （Jsc） and photoconversion efficiency （η） of PbS/Bi2S3（5）/TiO2 NAs electrode were 4.70 mA/cm and 1.13 %, respectively.
基金supported by the Institute of Science and High Technology and Environmental Sciences(No.1/1859)
文摘TiO2 nanowire arrays were successfully fabricated by liquid-phase deposition method using porous alumina templates. The obtained TiO2 nanowires were characterized using Raman spectroscopy, X-ray diffraction （XRD）, scanning electron microscopy （SEM）, field emission scanning electron microscopy （FE- SEM）, transmission electron microscopy （TEM）, and selected area electron diffraction （SAED） analysis. Results of electron microscopic observations indicated that the nanowires were smooth and uniform with a diameter of about 50-80 nm and several micrometers in length. SAED, Raman, and XRD mea- surements showed that TiO2 nanowires were single-crystalline with a pure rutile structure after heating at 800 ~C for 10 h. In this situation, the nanowire constituents grew preferentially along the 〈001〉 direction. Furthermore, the formation process and mechanistic study of the Ti02 nanowire arrays were proposed and discussed in detail. The nanowires are clearly produced by the deposition of TiO2 particles on the inner wall of the template nanochannels.
基金Supported by the National Natural Science Foundation of China(Grant No.50846069)
文摘Surface with TiO2 nanotube arrays(TNTAs)is superhydrophilic and of great specific area.This paper investigates the pool boiling characteristics at the thermal interface with TNTAs.The results show that the TNTAs interface can enhance the pool boiling heat transfer compared to the pure Ti metal plate.The bubbles formed at the initial nucleation state are very small and released in higher frequency.The pool boiling heat transfer enhancement at the TNTAs interface may be attributed to the high density of nucleate site,high intrinsic heating area of nanotubes layer,superhydrophilicity and the vertically oriented nanotube structure.
