Photoelectrochemical (PEC) hydrogen production holds great promise for applications in energy production. A novel strategy characterized by simplicity, stability, and high efficiency is developed to significantly boos...Photoelectrochemical (PEC) hydrogen production holds great promise for applications in energy production. A novel strategy characterized by simplicity, stability, and high efficiency is developed to significantly boost the PEC performance of TiO_(2) (anatase) nanotube arrays (TNTAs). This strategy entails a series of treatments, including a conventional anodic oxidation (etching) process, a primary annealing treatment, and a secondary annealing treatment via impregnation. As a result, nickel phosphide (Ni_(2)P) is composited onto well-ordered titanium dioxide (anatase) nanotube array photoanodes (Ni_(2)P/TNTAs), which exhibit hugely improved PEC H_(2) generation performance. A thorough and systematic investigation is conducted to comprehensively analyze the morphology, semiconductor band-gap structure, and PEC H_(2) production performance of the Ni_(2)P/TNTAs composites. The experimental results demonstrate that under identical experimental circumstances, the measured photocurrent density of the Ni_(2)P/TNTAs photoanode exhibits a 6.63-fold increase relative to that of TNTAs. The H_(2) production rate of Ni_(2)P/TNTAs reaches 182.96 μmol/cm^(2), 6.10 times higher than that of pure TNTAs. The excellent interfacial charge transfer pathway at the Ni_(2)P/TiO_(2) interface promotes photogenerated carrier separation and electron transfer from TiO_(2) to Ni_(2)P. This method offers a valuable reference for designing highly efficient PEC H_(2)-production catalysts.展开更多
The sensitive and selective monitoring of nitrogen dioxide(NO_(2))can have a significant impact on environmental monitoring and health protection.Unfortunately,commercial NO_(2)sensors largely suffer from poor detecti...The sensitive and selective monitoring of nitrogen dioxide(NO_(2))can have a significant impact on environmental monitoring and health protection.Unfortunately,commercial NO_(2)sensors largely suffer from poor detection sensitivity and high operating temperatures.In this study,we developed a sensitive roomtemperature NO_(2)sensor based on an n-n heterojunction comprised of a Cs_(2)AgInCl_(6)perovskite with chlorine vacancies(VCl)and TiO_(2)nanotube arrays(VCl-Cs_(2)AgInCl_(6)/TiO_(2)NTs).In this design,the large number of chlorine vacancies in the Cs_(2)AgInCl_(6)perovskite act as active sites for oxygen adsorption and the subsequent sensing reaction.Benefitting from the formation of the n-n type heterojunction and the onedimensional structure of the TiO_(2)nanotubes,the Fermi levels are aligned,thereby facilitating the efficient transport of charge carriers between the target gas and the sensing interface.The resulting VClCs_(2)Ag In Cl_(6)/TiO_(2)NTs demonstrate a high response of 7.26 toward 1 ppm of NO_(2)at room temperature,possess a detection limit as low as 20 ppb,and have outstanding performance stability.This work widens the application of perovskite materials and indicates their potential application in medical diagnostics,environmental monitoring,and smart sensing systems.展开更多
Zirconia nanotube array films(ZNAF)prepared by anodic oxidation method were used as immobilization materials for acridine orange(AO),rhodamine B(RB)and AO-RB systems.A comparative study on their fluorescence emission ...Zirconia nanotube array films(ZNAF)prepared by anodic oxidation method were used as immobilization materials for acridine orange(AO),rhodamine B(RB)and AO-RB systems.A comparative study on their fluorescence emission intensity,fluorescence resonance energy transfer(FRET)and fluorescence detection of nitrite in aqueous solutions and on immobilization films with ZNAF as carriers was carried out.Results demonstrate that the solution pH values and immobilization on ZNAF have a great influence on the per-formance of these fluorescent molecules.Compared with aqueous solutions,the fluorescence emission in-tensity of AO and RB is considerably increased by immobilization,which is 8.0 and 4.2 times higher than the original,respectively.The energy transfer efficiency(E)of the AO-RB system increases from 40.9%to 84.8%by loading it on ZNAF.Moreover,after immobilization onto ZNAF,the fluorescence detection performance of nitrite is also significantly improved.The limit of detection decreases from 0.95 ng/mL to 0.22 ng/mL and the sensitivity increases from 939.18 to 15,031.68 mL/μg through loading AO onto ZNAF.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
With increasing attention to personalized healthcare,miniaturized and easily implementable devices are desired for point-of-care testing(POCT).Herein,hydrophilic patterns were designed on freestanding TiO_(2)nanotube ...With increasing attention to personalized healthcare,miniaturized and easily implementable devices are desired for point-of-care testing(POCT).Herein,hydrophilic patterns were designed on freestanding TiO_(2)nanotube arrays(Ti NTs)as nanoreactors for a naked-eye colorimetric assay.With a high aspect ratio,TiN Ts can provide a long observation length combined with a limited volume.Moreover,by combining the photocatalytic property of TiO_(2)and spatiotemporal controllability of light,hydrophilic nanoreactors were fabricated with minimal volume,and thus the indicator and analyte are limited in a confined void by the hydrophobic surroundings,thus allowing a higher sensitivity for sensing.We believe the proposed sensing platform could provide a promising strategy in developing POCT devices for routine health monitoring.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
Titanium dioxide(TiO_2) has been investigated broadly as a stable,safe,and cheap anode material for sodium-ion batteries in recent years.However,the poor electronic conductivity and inherent sluggish sodium ion diffus...Titanium dioxide(TiO_2) has been investigated broadly as a stable,safe,and cheap anode material for sodium-ion batteries in recent years.However,the poor electronic conductivity and inherent sluggish sodium ion diffusion hinder its practical applications.Herein,a self-template and in situ vulcanization strategy is developed to synthesize self-supported hybrid nanotube arrays composed of nitrogen/sulfur-codoped carbon coated sulfur-doped TiO_2 nanotubes(S-TiO_2@NS-C) starting from H_2 Ti_2 O_5-H_2 O nanoarrays.The S-TiO_2@NS-C composite with one-dimensional nano-sized subunits integrates several merits.Specifically,sulfur doping strongly improves the Na~+ storage ability of TiO_2@C-N nanotubes by narrowing the bandgap of original TiO_2.Originating from the nanoarrays structures built from hollow nanotubes,carbon layer and sulfur doping,the sluggish Na~+ insertion/extraction kinetics is effectively improved and the volume variation of the electrode material is significantly alleviated.As a result,the S-TiO_2@NS-C nanoarrays present efficient sodium storage properties.The greatly improved sodium storage performances of S-TiO_2@NS-C nanoarrays confirm the importance of rational engineering and synthesis of hollow array architectures with higher complexity.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
V2 O5 nanotube arrays in porous atomic alumina （ PAA ） template were obtained from V2O5 sols prepared by melt quenching method. X-ray powder diffraction and selected area electron diffraction investigations demonstr...V2 O5 nanotube arrays in porous atomic alumina （ PAA ） template were obtained from V2O5 sols prepared by melt quenching method. X-ray powder diffraction and selected area electron diffraction investigations demonstrate that V2O5 nanotubes are orthorhombic. Results by scanning electron mieroscopy and transmission electron microscopy results shove that V2O5 nanotubes with a uniform diameter form highly ordered arrays. The diameter and length of the nanotubes depend on the pore diameter and the thickness of the PAA template used. It is proved that the sol-gel template process is a cost-saving , simple and readily-controlled method to prepare metal oxides nanomaterials .Owing to the quantum size effect. the optical absorption edge of V2O5 nanotubes in PAA ehibits a significant blue shift with respect to that of bulk V2O5.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
Controlling the charge transfer and thus enhancing the excitons’lifetime are the key to the realization of efficient photoelectrochemical(PEC)devices.Moreover,fabrication of flexible and collapsible sensors can great...Controlling the charge transfer and thus enhancing the excitons’lifetime are the key to the realization of efficient photoelectrochemical(PEC)devices.Moreover,fabrication of flexible and collapsible sensors can greatly facilitate the implementation of smart PEC sensing devices into practical applications.Herein,we sagely designed and successfully fabricated three-dimensional flexible Au nanoparticles-decorated TiO_(2) nanotube arrays(Au@TiO2)for the efficient PEC biosensing of glucose.The Schottky barrier derived from the Au@TiO2 heterostructure efficiently separates the charge carriers at the junction interfaces,thus greatly increasing the concentration and lifetime of holes left in the valence band of TiO2.The separated holes further evidently generate the active hydroxyl radicals,which can specifically recognize and oxidize glucose.As a result,Au@TiO_(2) exhibits excellent photoelectric activity and selectivity,far superior to TiO_(2) without decorated Au nanoparticles.In addition,such asymmetric Au@TiO_(2) system has been proved to feature the intrinsic flexibility nature,since its PEC biosensing performance is almost unaffected under indirect light irradiation and serious tensile strain.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
TiO_(2)has demonstrated outstanding performance in electrochemical advanced oxidation processes(EAOPs)due to its structural stability and high oxygen overpotential.However,there is still much room for improving its el...TiO_(2)has demonstrated outstanding performance in electrochemical advanced oxidation processes(EAOPs)due to its structural stability and high oxygen overpotential.However,there is still much room for improving its electrochemical activity.Herein,narrow bandgap manganese oxide(MnO_(x))was composited with TiO_(2)nanotube arrays(TiO_(2)NTAs)that in-situ oxidized on porous Ti sponge,forming the MnO_(x)-TiO_(2)NTAs anode.XANES and XPS analysis further proved that the composition of MnO_(x)is Mn2O3.Electrochemical characterizations revealed that increasing the composited concentration of MnO_(x)can improve the conductivity and reduce oxygen evolution potential so as to improve the electrochemical activity of the composited MnO_(x)-TiO_(2)NTAs anode.Meanwhile,the optimal degradation rate of benzoic acid(BA)was achieved using MnO_(x)-TiO_(2)NTAs with a MnO_(x)concentration of 0.1 mmol L^(-1),and the role of MnO_(x)was proposed based on DFT calculation.Additionally,the required electrical energy(EE/O)to destroy BA was optimized by varying the composited concentration of MnO_(x)and the degradation voltage.These quantitative results are of great significance for the design and application of high-performance materials for EAOPs.展开更多
CuFe2O4 nanotube arrays with different outer diameters were synthesized in anodic aluminum oxide templates through sol-gel techniques followed by heating treatment processes. The morphology of the nanotube arrays was ...CuFe2O4 nanotube arrays with different outer diameters were synthesized in anodic aluminum oxide templates through sol-gel techniques followed by heating treatment processes. The morphology of the nanotube arrays was investigated by field emission scanning electron microscope and transmission electron microscopy, suggesting that the nanotube arrays are ordered and uniform. The X-ray diffraction results indicate that the crystal structure of the nanotube arrays is polycrystalline with a spinel-type structure. The measurements of magnetic properties indicate that CuFe2O4 nanotube arrays with outer diameter of 200 nm exhibit magnetic anisotropy with easy magnetization direction along the axis of nanotubes.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
To extend the absorption capability of TiO_2 into visible light region and inhibit the recombination of photogenerated electrons and holes,we put forward an effective strategy of the coupling of TiO_2 with a suitable ...To extend the absorption capability of TiO_2 into visible light region and inhibit the recombination of photogenerated electrons and holes,we put forward an effective strategy of the coupling of TiO_2 with a suitable semiconductor that possesses a narrow band gap.Meanwhile,Ag_3PO_4-TiO_2 heterostructuralnanotube arrays were prepared by the two-step anodic oxidation to obtain the TiO_2 nanotube arrays and then by a deposition-precipitation method to load Ag_3PO_4.The samples were characterized by field emission scanning electron microscopy（FESEM）,energy dispersive spectrometry（EDS）,X-ray diffraction（XRD）,and UV-vis diffuse reflectance spectroscopy（UV-vis DRS）.The experimentalresults showed that Ag_3PO_4 nanoparticles were uniformly dispersed on the highly ordered TiO_2 nanotube arrays,which increased the visible-light absorption of TiO_2 photocatalyst.The photocurrent density and photocatalytic degradation of methylorange indicated that the performance of Ag_3PO_4-TiO_2 heterostructuralnanotube arrays was better than that of the TiO_2 nanotube arrays,which could be attributed to the effective electron-hole separation and the improved utilization of visible light.展开更多
Well-ordered TiO_(2)nanotube arrays(TNTAs)decorated with graphitic carbon nitride(g-C_(3)N_(4))were fabricated by anodic oxidization and calcination process.First,TNTAs were prepared via the anodic oxidation of Ti foi...Well-ordered TiO_(2)nanotube arrays(TNTAs)decorated with graphitic carbon nitride(g-C_(3)N_(4))were fabricated by anodic oxidization and calcination process.First,TNTAs were prepared via the anodic oxidation of Ti foil in glycerol solution containing fluorinion and 20%deionized water.Subsequently,g-C_3N_4 film was hydrothermally grown on TNTAs via the hydrogen-bonded cyanuric acid melamine supramolecular complex.The results showed that g-C_(3)N_(4)was successfully decorated on the TNTAs and the g-C_(3)N_(4)/TNTAs served as an efficient and stable photoanode for photoelectrochemical water splitting.The facile deposition method enables the fabrication of efficient and low-cost photoanodes for renewable energy applications.展开更多
基金financial support of the Natural Science Foundation of Fujian Province(2023H0046)the XMIREM autonomously deployment project(2023CX10,2023GG01)+3 种基金the Science and Technology Service Network Initiative from Chinese Academy of Science(STS2024T3071)the National Natural Science Foundation of China(22275185,22272069,22472074)the Major Research Project of Xiamen(3502Z20191015)the Fujian Science&Technology Innovation Laboratory for Optoelectronic Information。
文摘Photoelectrochemical (PEC) hydrogen production holds great promise for applications in energy production. A novel strategy characterized by simplicity, stability, and high efficiency is developed to significantly boost the PEC performance of TiO_(2) (anatase) nanotube arrays (TNTAs). This strategy entails a series of treatments, including a conventional anodic oxidation (etching) process, a primary annealing treatment, and a secondary annealing treatment via impregnation. As a result, nickel phosphide (Ni_(2)P) is composited onto well-ordered titanium dioxide (anatase) nanotube array photoanodes (Ni_(2)P/TNTAs), which exhibit hugely improved PEC H_(2) generation performance. A thorough and systematic investigation is conducted to comprehensively analyze the morphology, semiconductor band-gap structure, and PEC H_(2) production performance of the Ni_(2)P/TNTAs composites. The experimental results demonstrate that under identical experimental circumstances, the measured photocurrent density of the Ni_(2)P/TNTAs photoanode exhibits a 6.63-fold increase relative to that of TNTAs. The H_(2) production rate of Ni_(2)P/TNTAs reaches 182.96 μmol/cm^(2), 6.10 times higher than that of pure TNTAs. The excellent interfacial charge transfer pathway at the Ni_(2)P/TiO_(2) interface promotes photogenerated carrier separation and electron transfer from TiO_(2) to Ni_(2)P. This method offers a valuable reference for designing highly efficient PEC H_(2)-production catalysts.
基金supported by the National Natural Science Foundation of China(No.22374015)the Fundamental Research Funds for the Central Universities(N2424020)+1 种基金Liaoning Province Foundation for Distinguished Young Scholars(No.1727146584490,to Y.-Y.Song)Liaoning Binhai laboratory(No.LBLG-2024-02)。
文摘The sensitive and selective monitoring of nitrogen dioxide(NO_(2))can have a significant impact on environmental monitoring and health protection.Unfortunately,commercial NO_(2)sensors largely suffer from poor detection sensitivity and high operating temperatures.In this study,we developed a sensitive roomtemperature NO_(2)sensor based on an n-n heterojunction comprised of a Cs_(2)AgInCl_(6)perovskite with chlorine vacancies(VCl)and TiO_(2)nanotube arrays(VCl-Cs_(2)AgInCl_(6)/TiO_(2)NTs).In this design,the large number of chlorine vacancies in the Cs_(2)AgInCl_(6)perovskite act as active sites for oxygen adsorption and the subsequent sensing reaction.Benefitting from the formation of the n-n type heterojunction and the onedimensional structure of the TiO_(2)nanotubes,the Fermi levels are aligned,thereby facilitating the efficient transport of charge carriers between the target gas and the sensing interface.The resulting VClCs_(2)Ag In Cl_(6)/TiO_(2)NTs demonstrate a high response of 7.26 toward 1 ppm of NO_(2)at room temperature,possess a detection limit as low as 20 ppb,and have outstanding performance stability.This work widens the application of perovskite materials and indicates their potential application in medical diagnostics,environmental monitoring,and smart sensing systems.
基金supported by the National Natural Science Foundation of China(No.51972095).
文摘Zirconia nanotube array films(ZNAF)prepared by anodic oxidation method were used as immobilization materials for acridine orange(AO),rhodamine B(RB)and AO-RB systems.A comparative study on their fluorescence emission intensity,fluorescence resonance energy transfer(FRET)and fluorescence detection of nitrite in aqueous solutions and on immobilization films with ZNAF as carriers was carried out.Results demonstrate that the solution pH values and immobilization on ZNAF have a great influence on the per-formance of these fluorescent molecules.Compared with aqueous solutions,the fluorescence emission in-tensity of AO and RB is considerably increased by immobilization,which is 8.0 and 4.2 times higher than the original,respectively.The energy transfer efficiency(E)of the AO-RB system increases from 40.9%to 84.8%by loading it on ZNAF.Moreover,after immobilization onto ZNAF,the fluorescence detection performance of nitrite is also significantly improved.The limit of detection decreases from 0.95 ng/mL to 0.22 ng/mL and the sensitivity increases from 939.18 to 15,031.68 mL/μg through loading AO onto ZNAF.
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the financial support from the National Natural Science Foundation of China(Nos.21874013,22204016 and 22074013)the Fundamental Research Funds for the Central Universities(Nos.N2005027,N2105018,and N2205005)。
文摘With increasing attention to personalized healthcare,miniaturized and easily implementable devices are desired for point-of-care testing(POCT).Herein,hydrophilic patterns were designed on freestanding TiO_(2)nanotube arrays(Ti NTs)as nanoreactors for a naked-eye colorimetric assay.With a high aspect ratio,TiN Ts can provide a long observation length combined with a limited volume.Moreover,by combining the photocatalytic property of TiO_(2)and spatiotemporal controllability of light,hydrophilic nanoreactors were fabricated with minimal volume,and thus the indicator and analyte are limited in a confined void by the hydrophobic surroundings,thus allowing a higher sensitivity for sensing.We believe the proposed sensing platform could provide a promising strategy in developing POCT devices for routine health monitoring.
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 supports provided by the National Natural Science Foundation of China (21871164)the Taishan Scholar Project Foundation of Shandong Province (ts20190908, ts201511004)the Natural Science Foundation of Shandong Province (ZR2019MB024)。
文摘Titanium dioxide(TiO_2) has been investigated broadly as a stable,safe,and cheap anode material for sodium-ion batteries in recent years.However,the poor electronic conductivity and inherent sluggish sodium ion diffusion hinder its practical applications.Herein,a self-template and in situ vulcanization strategy is developed to synthesize self-supported hybrid nanotube arrays composed of nitrogen/sulfur-codoped carbon coated sulfur-doped TiO_2 nanotubes(S-TiO_2@NS-C) starting from H_2 Ti_2 O_5-H_2 O nanoarrays.The S-TiO_2@NS-C composite with one-dimensional nano-sized subunits integrates several merits.Specifically,sulfur doping strongly improves the Na~+ storage ability of TiO_2@C-N nanotubes by narrowing the bandgap of original TiO_2.Originating from the nanoarrays structures built from hollow nanotubes,carbon layer and sulfur doping,the sluggish Na~+ insertion/extraction kinetics is effectively improved and the volume variation of the electrode material is significantly alleviated.As a result,the S-TiO_2@NS-C nanoarrays present efficient sodium storage properties.The greatly improved sodium storage performances of S-TiO_2@NS-C nanoarrays confirm the importance of rational engineering and synthesis of hollow array architectures with higher complexity.
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Funded bythe Key Project of Chinese Ministry of Education(No.104207)andthe National Natural Science Foundation of China(No.50372046)
文摘V2 O5 nanotube arrays in porous atomic alumina （ PAA ） template were obtained from V2O5 sols prepared by melt quenching method. X-ray powder diffraction and selected area electron diffraction investigations demonstrate that V2O5 nanotubes are orthorhombic. Results by scanning electron mieroscopy and transmission electron microscopy results shove that V2O5 nanotubes with a uniform diameter form highly ordered arrays. The diameter and length of the nanotubes depend on the pore diameter and the thickness of the PAA template used. It is proved that the sol-gel template process is a cost-saving , simple and readily-controlled method to prepare metal oxides nanomaterials .Owing to the quantum size effect. the optical absorption edge of V2O5 nanotubes in PAA ehibits a significant blue shift with respect to that of bulk V2O5.
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financially supported by the National Natural Science Foundation of China(Nos.61764003 and 51462008)the Major Science and Technology Planning Project of Hainan Province(No.ZDKJ201810)。
文摘Controlling the charge transfer and thus enhancing the excitons’lifetime are the key to the realization of efficient photoelectrochemical(PEC)devices.Moreover,fabrication of flexible and collapsible sensors can greatly facilitate the implementation of smart PEC sensing devices into practical applications.Herein,we sagely designed and successfully fabricated three-dimensional flexible Au nanoparticles-decorated TiO_(2) nanotube arrays(Au@TiO2)for the efficient PEC biosensing of glucose.The Schottky barrier derived from the Au@TiO2 heterostructure efficiently separates the charge carriers at the junction interfaces,thus greatly increasing the concentration and lifetime of holes left in the valence band of TiO2.The separated holes further evidently generate the active hydroxyl radicals,which can specifically recognize and oxidize glucose.As a result,Au@TiO_(2) exhibits excellent photoelectric activity and selectivity,far superior to TiO_(2) without decorated Au nanoparticles.In addition,such asymmetric Au@TiO_(2) system has been proved to feature the intrinsic flexibility nature,since its PEC biosensing performance is almost unaffected under indirect light irradiation and serious tensile strain.
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the support from the Brook Byers Institute for Sustainable Systems,Hightower ChairGeorgia Research Alliance at the Georgia Institute of Technology。
文摘TiO_(2)has demonstrated outstanding performance in electrochemical advanced oxidation processes(EAOPs)due to its structural stability and high oxygen overpotential.However,there is still much room for improving its electrochemical activity.Herein,narrow bandgap manganese oxide(MnO_(x))was composited with TiO_(2)nanotube arrays(TiO_(2)NTAs)that in-situ oxidized on porous Ti sponge,forming the MnO_(x)-TiO_(2)NTAs anode.XANES and XPS analysis further proved that the composition of MnO_(x)is Mn2O3.Electrochemical characterizations revealed that increasing the composited concentration of MnO_(x)can improve the conductivity and reduce oxygen evolution potential so as to improve the electrochemical activity of the composited MnO_(x)-TiO_(2)NTAs anode.Meanwhile,the optimal degradation rate of benzoic acid(BA)was achieved using MnO_(x)-TiO_(2)NTAs with a MnO_(x)concentration of 0.1 mmol L^(-1),and the role of MnO_(x)was proposed based on DFT calculation.Additionally,the required electrical energy(EE/O)to destroy BA was optimized by varying the composited concentration of MnO_(x)and the degradation voltage.These quantitative results are of great significance for the design and application of high-performance materials for EAOPs.
基金Funded by National Science Fund for Distinguished Young Scholars (No.50925103)the Key Project of Chinese Ministry of Education (No. 309027)+1 种基金the Fund for Academic Newcomer of PhD of Lanzhou Universitythe National Natural Science Foundation of China(No.11034004)
文摘CuFe2O4 nanotube arrays with different outer diameters were synthesized in anodic aluminum oxide templates through sol-gel techniques followed by heating treatment processes. The morphology of the nanotube arrays was investigated by field emission scanning electron microscope and transmission electron microscopy, suggesting that the nanotube arrays are ordered and uniform. The X-ray diffraction results indicate that the crystal structure of the nanotube arrays is polycrystalline with a spinel-type structure. The measurements of magnetic properties indicate that CuFe2O4 nanotube arrays with outer diameter of 200 nm exhibit magnetic anisotropy with easy magnetization direction along the axis of nanotubes.
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Funded by the Natural Science Foundation of Hubei Province(2012FFB05105)
文摘To extend the absorption capability of TiO_2 into visible light region and inhibit the recombination of photogenerated electrons and holes,we put forward an effective strategy of the coupling of TiO_2 with a suitable semiconductor that possesses a narrow band gap.Meanwhile,Ag_3PO_4-TiO_2 heterostructuralnanotube arrays were prepared by the two-step anodic oxidation to obtain the TiO_2 nanotube arrays and then by a deposition-precipitation method to load Ag_3PO_4.The samples were characterized by field emission scanning electron microscopy（FESEM）,energy dispersive spectrometry（EDS）,X-ray diffraction（XRD）,and UV-vis diffuse reflectance spectroscopy（UV-vis DRS）.The experimentalresults showed that Ag_3PO_4 nanoparticles were uniformly dispersed on the highly ordered TiO_2 nanotube arrays,which increased the visible-light absorption of TiO_2 photocatalyst.The photocurrent density and photocatalytic degradation of methylorange indicated that the performance of Ag_3PO_4-TiO_2 heterostructuralnanotube arrays was better than that of the TiO_2 nanotube arrays,which could be attributed to the effective electron-hole separation and the improved utilization of visible light.
基金financial support from the National Natural Science Foundation of China(Nos.51702025,51574047)Natural Science Foundation of Jiangsu Province(Nos.BK20160277,BK20150259)
文摘Well-ordered TiO_(2)nanotube arrays(TNTAs)decorated with graphitic carbon nitride(g-C_(3)N_(4))were fabricated by anodic oxidization and calcination process.First,TNTAs were prepared via the anodic oxidation of Ti foil in glycerol solution containing fluorinion and 20%deionized water.Subsequently,g-C_3N_4 film was hydrothermally grown on TNTAs via the hydrogen-bonded cyanuric acid melamine supramolecular complex.The results showed that g-C_(3)N_(4)was successfully decorated on the TNTAs and the g-C_(3)N_(4)/TNTAs served as an efficient and stable photoanode for photoelectrochemical water splitting.The facile deposition method enables the fabrication of efficient and low-cost photoanodes for renewable energy applications.
