A novel titanium dioxide （TiO2） film comprising both nanotubes and nanopaticles was fabricated by an anodization process of the modified titanium. The local electric field at the anodized surface was simulated and i...A novel titanium dioxide （TiO2） film comprising both nanotubes and nanopaticles was fabricated by an anodization process of the modified titanium. The local electric field at the anodized surface was simulated and its influence on the morphology of the TiO2 film was discussed. The results show that the electric field strength is enhanced by the covering. The growth rate of TiO2 increases with the assist of the local electric field. However, TiO2 dissolution is hindered since the local electric field prevents [TiF6]6- from diffusing. It means that the balance condition for the formation of nanotubes is broken, and TiO2 nanoparticles are formed. Moreover, the crystal structure of the TiO2 film was confirmed using X-ray diffraction and Raman analysis. The anatase is a main phase for the proposed film.展开更多
A layer of graphene(GR)particles was successfully deposited at the interface between Co(OH)2 nanoparticles and TiO2 nanotubes,aiming to improve the photoelectrochemical performance of the large-bandgap semiconductor T...A layer of graphene(GR)particles was successfully deposited at the interface between Co(OH)2 nanoparticles and TiO2 nanotubes,aiming to improve the photoelectrochemical performance of the large-bandgap semiconductor TiO2.The obtained Co(OH)2/GR/TiO2 was extensively characterized by X-ray diffraction(XRD),scanning electron microscopy(SEM),transmission electron microscopy(TEM),X-ray photoelectron spectroscopy(XPS),UV–vis absorption spectra and photoluminescence(PL)emission spectra.Electrochemical impedance spectra,photogenerated potential-time(E-t),photocurrent density-time(i-t)and i-E curves and open circuit potential(OCP)curves were measured to investigate the photoelectrochemical activities and photogenerated cathodic protection properties.The results revealed that Co(OH)2/GR/TiO2 exhibits excellent photoelectrochemical and photogenerated cathodic performance due to synergistic effect between Co(OH)2 and graphene.Co(OH)2 and graphene co-modified TiO2 photoanode could provide an effective protection for 304 stainless steel(304 SS)in 3.5 wt%Na Cl solution for 12 h,which would be promising for future practical applications in the field of marine corrosion protection.展开更多
Two-dimensional (2D) ultrathin MoS2-modified black Ti^3+-TiO2 nanotubes were fabricated using an electrospinning-hydrothermal treatment-reduction method.Bare TiO2 nanotubes were fabricated via electrospinning.Then,2D ...Two-dimensional (2D) ultrathin MoS2-modified black Ti^3+-TiO2 nanotubes were fabricated using an electrospinning-hydrothermal treatment-reduction method.Bare TiO2 nanotubes were fabricated via electrospinning.Then,2D MoS2 lamellae were grown on the surface of the nanotubes and Ti^3+/Ov ions were introduced by reduction.The photocatalytic performance of the 2D MoS2/Ti^3+-TiO2 nanotubes was^15 times better than that of TiO2.The HER enhancement of the MoS2/Ti^3+-TiO2 nanotubes can be attributed to the Pt-like behavior of 2D MoS2 and the presence of Ti^3+-ions,which facilitated the quick diffusion of the photogenerated electrons to water,reducing the H2 activation barrier.The presence of Ov ions in the nanotubes and their hollow structure increased their solar utilization.展开更多
We report the development of a novel visible response BiVO_4/TiO_2(N_2) nanotubes photoanode for photoelectrocatalytic applications. The nitrogen-treated TiO_2 nanotube shows a high carrier concentration rate, thus re...We report the development of a novel visible response BiVO_4/TiO_2(N_2) nanotubes photoanode for photoelectrocatalytic applications. The nitrogen-treated TiO_2 nanotube shows a high carrier concentration rate, thus resulting in a high efficient charge transportation and low electron–hole recombination in the TiO_2–BiVO_4. Therefore, the BiVO_4/TiO_2(N_2) NTs photoanode enabled with a significantly enhanced photocurrent of 2.73 mA cm^(-2)(at 1 V vs. Ag/Ag Cl) and a degradation efficiency in the oxidation of dyes under visible light. Field emission scanning electron microscopy, X-ray diffractometry, energy-dispersive X-ray spectrometer, and UV–Vis absorption spectrum were conducted to characterize the photoanode and demonstrated the presence of both metal oxides as a junction composite.展开更多
IrO2 and IrRuOx(Ir:Ru 60:40 at%),supported by 50 wt%onto titania nanotubes(TNTs)and(3 at%Nb)Nb-doped titania nanotubes(Nb-TNTs),as electrocatalysts for the oxygen evolution reaction(OER),were synthesized and character...IrO2 and IrRuOx(Ir:Ru 60:40 at%),supported by 50 wt%onto titania nanotubes(TNTs)and(3 at%Nb)Nb-doped titania nanotubes(Nb-TNTs),as electrocatalysts for the oxygen evolution reaction(OER),were synthesized and characterized by means of structural,surface analytical and electrochemical techniques.Nb doping of titania significantly increased the surface area of the support from 145(TNTs)to 260 m2g-1(Nb-TNTs),which was significantly higher than those of the Nb-doped titania supports previously reported in the literature.The surface analytical techniques showed good dispersion of the catalysts onto the supports.The X-ray photoelectron spectroscopy analyses showed that Nb was mainly in the form of Nb(IV)species,the suitable form to behave as a donor introducing free electrons to the conduction band of titania.The redox transitions of the cyclic voltammograms,in agreement with the XPS results,were found to be reversible.Despite the supported materials presented bigger crystallite sizes than the unsupported ones,the total number of active sites of the former was also higher due to their better catalyst dispersion.Considering the outer and the total charges of the cyclic voltammograms in the range 0.1–1.4 V,stability and electrode potentials at given current densities,the preferred catalyst was Ir O2 supported on the Nb-TNTs.The electrode potentials corresponding to given current densities were between the smallest ones given in the literature despite the small oxide loading used in this work and its Nb doping,thus making the Nb-TNTs-supported IrO2 catalyst a promising candidate for the OER.The good dispersion of IrO2,high specific surface area of the Nb-doped supports,accessibility of the electroactive centers,increased stability due to Nb doping and electron donor properties of the Nb(IV)oxide species were considered the main reasons for its good performance.展开更多
Controllable synthesis of insertion-type anode materials with beneficial micro-and nanostructures is a promising approach for the synthesis of sodium-ion storage devices with high-reactivity and excellent electrochemi...Controllable synthesis of insertion-type anode materials with beneficial micro-and nanostructures is a promising approach for the synthesis of sodium-ion storage devices with high-reactivity and excellent electrochemical performance.In this study,we developed a sacrificial-templating route to synthesize TiO_(2)@N-doped carbon nanotubes(TiO_(2)@NC-NTs)with excellent electrochemical performance.The asprepared mesoporous TiO_(2)@NC-NTs with tiny nanocrystals of anatase TiO_(2) wrapped in N-doped carbon layers showed a well-defined tube structure with a large specific surface area of 198 m^(2) g^(-1) and a large pore size of~5 nm.The TiO_(2)@NC-NTs delivered high reversible capacities of 158 m A h g^(-1) at 2 C(1 C=335 m A g^(-1))for 2200 cycles and 146 m A h g^(-1) at 5 C for 4000 cycles,as well as an ultrahigh rate capability of up to 40 C with a capacity of 98 m A h g^(-1).Even at a high current density of 10 C,a capacity of 138 m A h g^(-1) could be delivered over 10,000 cycles.Thus,the synthesis of mesoporous TiO_(2)@NC-NTs was demonstrated to be an efficient approach for developing electrode materials with high sodium storage and long cycle life.展开更多
TiO2 nanotubes(NT)has been demonstrated its potential in orthopaedic applications due to its enhanced surface wettability and bio-osteointegration.However,the fretting biocorrosion is the main concern that limited its...TiO2 nanotubes(NT)has been demonstrated its potential in orthopaedic applications due to its enhanced surface wettability and bio-osteointegration.However,the fretting biocorrosion is the main concern that limited its successfully application in orthopaedic application.In this study,a structure optimised thin TiO2 nanotube(SONT)layer was successfully created on Ti6Al4V bone screw,and its fretting corrosion performance was investigated and compared to the pristine Ti6Al4V bone screws and NT decorated screw in a bone-screw fretting simulation rig.The results have shown that the debonding TiO2 nanotube from the bone screw reduced significantly,as a result of structure optimisation.The SONT layer also exhibited enhanced bio-corrosion resistance compared pristine bone screw and conventionally NT modified bone screw.It is postulated that interfacial layer between TiO2 nanotube and Ti6Al4V substrate,generated during structure optimisation process,enhanced bonding of TiO2 nanotube layer to the Ti6Al4V bone screws that leading to the improvement in fretting corrosion resistance.The results highlighted the potential SONT in orthopaedic application as bone fracture fixation devices.展开更多
Pt-TiO2 nanotubes with tube diameter of -120 nm and uniformly dispersed Pt particles（size of -2 nm） were successfully synthesized via a carbon nanotube（CNT） templating method followed by a photo-deposition process...Pt-TiO2 nanotubes with tube diameter of -120 nm and uniformly dispersed Pt particles（size of -2 nm） were successfully synthesized via a carbon nanotube（CNT） templating method followed by a photo-deposition processing of Pt nanoparticles. The as-obtained Pt-TiO2 NTs possess both enhanced visible light absorption and reduced recombination of photogenerated electrons and holes. These merits boost the Pt-TiO2 NTs an excellent photocatalytic material toward photooxidation of a variety of low molecular hydrocarbons under atmospheric environment.展开更多
We report the in vitro cell test and in vivo animal test results of titanium oxide nanotubes (TiO2 NTs) as a potential therapeutic agent used for cancer thermotherapy in combination with near-infrared (NIR) laser. The...We report the in vitro cell test and in vivo animal test results of titanium oxide nanotubes (TiO2 NTs) as a potential therapeutic agent used for cancer thermotherapy in combination with near-infrared (NIR) laser. The in vitro cell test results show that both the cells exposed to NIR laser without TiO2 NTs treatment and the cells treated with TiO2 NTs but not with NIR irradiation had cell viabilities higher than 96%. Combination of these two techniques, however, shows cell viability less than 1%. The cell death rate strongly depended on the concentration of TiO2 NTs. Also, the cell deaths were mostly due to necrosis but partly due to late apoptosis. The in vivo animal test results show that tumor cells can be completely destroyed without nearly giving damage to surrounding healthy cells by an injection of an adequate amount of TiO2 NTs/NaCl suspension and a subsequent single continuous laser treatment at a moderately low laser illumina-tion intensity for the exposure time optimized for the tumor size. These results suggest that TiO2 NTs can be effectively utilized as a therapeutic agent for cancer thermotherapy due to their excellent photothermal property and high bio-compatibility.展开更多
A novel catalyst,TiO2 nanotubes(TiO2 NTs)composite decorated by CuO and CeO2 particles,was prepared by a simple and cost-effective method.The TiO2 NTs were fabricated by the hydrothermal method,and CuO and CeO2 partic...A novel catalyst,TiO2 nanotubes(TiO2 NTs)composite decorated by CuO and CeO2 particles,was prepared by a simple and cost-effective method.The TiO2 NTs were fabricated by the hydrothermal method,and CuO and CeO2 particles loaded onto TiO2 NTs(CuO/CeO2@TiO2 NTs)were prepared by the water bath heating method.The CuO/CeO2@TiO2 NTs were investigated and characterized by transmission electron microscope(TEM),energy dispersive spectrometer(EDS),photoluminescence(PL),X-ray diffractometer(XRD)and ultraviolet-visible light diffuse reflectance spectrum(UV-Vis DRS).Both the p-n heterojunction formed at the p-CuO and n-TiO2 interfaces and the highly induced electron transfer of CeO2 can greatly promote the separation of electrons-holes.Therefore,CuO/CeO2@TiO2 NTs show enhanced absorption and have potential applications in photocatalysis.展开更多
Nitrogen-doped TiO2 nanotubes(TNTs)were prepared by ion implantation and anodic oxidation.The prepared samples were applied in photocatalytic(PC)oxidation of methyl blue,rhodamine B,and bisphenol A under light irradia...Nitrogen-doped TiO2 nanotubes(TNTs)were prepared by ion implantation and anodic oxidation.The prepared samples were applied in photocatalytic(PC)oxidation of methyl blue,rhodamine B,and bisphenol A under light irradiation.To explore the influence of doped ions on the band and electronic structure of TiO2,computer simulations were performed using the VASP code implementing spin-polarized density functional theory(DFT).Both substitutional and interstitial nitrogen atoms were considered.The experimental and computational results propose that the electronic structure of TiO2 was modified because of the emergence of impurity states in the band gap by introducing nitrogen into the lattice,leading to the absorption of visible light.The synergy effects of tubular structures and doped nitrogen ions were responsible for highly efficient and stable PC activities induced by visible and ultraviolet(UV)light.展开更多
TiO2 nanotubes on Ti metal surface were prepared by the electrochemical anodization method. Then, nanosilver was deposited onto the nanotubes by the electroless dip coating and the anodization. The obtained TiO2 nanot...TiO2 nanotubes on Ti metal surface were prepared by the electrochemical anodization method. Then, nanosilver was deposited onto the nanotubes by the electroless dip coating and the anodization. The obtained TiO2 nanotubes were examined by using scanning electron microscopy, atomic force microscopy, Fourier transform infrared spectroscopy, X-ray diffraction, cyclic voltammetry, and UV–Vis. The electrochemical band gap（Eg^CV） of the nanosilver-coated TiO2 nanotubes prepared by the anodization was found as 1.54 eV. Using the UV–Vis measurements, the optical band gap energy（Eg^op.） was calculated as 1.51 eV for the Ag/TiO2 nanotubes obtained by electroless dip coating. The electrical conductivity of the TiO2 nanotubes also increased from 3.0 × 10^-4 to 34.7 S/cm after nano Ag deposition by the anodization method.These Ag/TiO2 nanotubes with low band gap and high electrical conductivity are desirable for the applications in electronics, Li-ion batteries, and solar cells.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
Direct utilization of co-existed ferrous oxide(FeO)dust in CO_(2)flue gas from the steel industry to product value-added materials is yet to be established.Inspired by the form of CaO-CaCO_(3)as natural carbon cycle a...Direct utilization of co-existed ferrous oxide(FeO)dust in CO_(2)flue gas from the steel industry to product value-added materials is yet to be established.Inspired by the form of CaO-CaCO_(3)as natural carbon cycle and the high oxide dissolution capacity of molten salts,CaO is herein introduced into the affordable molten NaCl-CaCl_(2)-FeO salt to generate CO_(3)^(2-)through an efficient capture of CO_(2).The subsequent coelectrolysis of FeO and CO_(3)^(2-)successfully produces cathodic Fe-encapsulated carbon nanotubes(Fe@CNT)with enhanced energy efficiency(current efficiency of 83.1%for CO_(2)reduction and energy consumption of 22.49 kWh kg^(1)for Fe@CNT generation).The in-situ capture of CO_(2)by O^(2)generated from the electro-deoxidation of FeO bridges the electrolysis of CO_(2)and FeO,rendering the enhanced current efficiency of the co-electrolysis and template-free generation of Fe@CNT.When evaluated as functional materials for electromagnetic wave absorption,the Fe@CNT integrates dielectric loss of CNT and electromagnetic loss from Fe.The Fe well-defined in CNT induces the synergistic loss and further improves the impedance matching,resulting in excellent electromagnetic wave absorption performance.The coelectrolysis establishes a promising strategy for converting CO_(2)into highly functional materials directly from CO_(2)-containing flue gas from steel industrial without dust removal.展开更多
Copper is a versatile material,commonly utilized in power transmission and electronic devices,but its relative high reactivity necessitates a long-lasting protective technique.Here,we report a method that combines pla...Copper is a versatile material,commonly utilized in power transmission and electronic devices,but its relative high reactivity necessitates a long-lasting protective technique.Here,we report a method that combines plasma-enhanced non-equilibrium magnetron sputtering physical vapor deposition(PEUMS-PVD)and anodization to construct a self-healing three-dimensional Ti/Al-doped TiO_(2)nanotubes/Ti_(3)AlC_(2)coating on the surface of Cu substrates.This novel strategy enhances the corrosion resistance of copper substrates in marine environments,with corrosion current densities of up to 4.5643×10^(−8)A/cm^(2).Among them,the doping of nano-aluminum particles makes the coating self-healing.The mechanistic analysis of the corrosion behaviors during early immersion experiments was conducted using electrochemical noise,and revealed that during the initial stages of coating immersion,uniform corrosion predominates,with a minor occurrence of localized corrosion.展开更多
The size tuning of one-dimensional(1D)spatially confined electrocatalysts with abundant exposed active sites is still a huge challenge for electrocatalytic hydrogen/oxygen evolution reactions(HER/OER)and overall water...The size tuning of one-dimensional(1D)spatially confined electrocatalysts with abundant exposed active sites is still a huge challenge for electrocatalytic hydrogen/oxygen evolution reactions(HER/OER)and overall water splitting(OWS).Herein,we construct CoPNi_(2)P heterostructure embedded ultrafine N-doped carbon nanotubes(CoP-Ni_(2)P@U-NCNTs/NF)with a diameter size of about 50 nm from 2D cobalt-based zeolitic imidazolate framework(Co-ZIF-L/NF)via phosphorylation strategy,while Co-Ni embedded N-doped carbon nanotubes with a diameter of about 200 nm are constructed via carbonization.The size-tuned CoP-Ni_(2)P@U-NCNTs/NF possesses abundant active sites and electron transport pathways,and the stability of CoP-Ni_(2)P heterostructure is improved by carbon coating.Density functional theory(DFT)calculation results verify that the Ni_(2)P and CoP heterojunction synergistic ally promotes the electron redistribution of the Co-Ni to optimize Gibbs free energy of H*(ΔGH*).Meanwhile,the NCNTs-confined CoP-Ni_(2)P induced by phosphating accelerates the reconstruction of the CoOOH-NiOOH compared with Ni-Co,therebyboosting the reaction kinetics of efficient OWS due to the reduced reaction energy barrier of O-O coupling.As expected,the CoP-Ni_(2)P@U-NCNTs/NF favors a low overpotential of 67/203 mV@10 mA cm^(-2)for the HER/OER,realizing an ultralow cell voltage of 1.52V@10 mA cm^(-2)for OWS and long-term durability at various current densities.This work provides a feasible approach to tuning the composition and structure of highefficiency electrocatalysts for the production of green hydrogen.展开更多
Both Ti foil and porous Ti were anodized in 0.5%HF and in ethylene glycol electrolyte containing 0.5%NH4F(mass fraction) separately. The results show that TiO2 nanotubes can be formed on Ti foil by both processes, whe...Both Ti foil and porous Ti were anodized in 0.5%HF and in ethylene glycol electrolyte containing 0.5%NH4F(mass fraction) separately. The results show that TiO2 nanotubes can be formed on Ti foil by both processes, whereas TiO2 nanotubes can be formed on porous Ti only in the second process. The overhigh current density led to the failure of the formation nanotubes on porous Ti in 0.5%HF electrolyte. TiO2 nanotubes were characterized by SEM and XRD. TiO2 nanotubes on porous Ti were thinner than those on Ti foil. Anatase was formed when TiO2 nanotubes were annealed at 400 °C and fully turned into rutile at 700 °C. To obtain good photodegradation, the optimal heat treatment temperature of TiO2 nanotubes was 450 °C. The porosity of the substrates influenced photodegradation properties. TiO2 nanotubes on porous Ti with 60% porosity had the best photodegradation.展开更多
文摘A novel titanium dioxide （TiO2） film comprising both nanotubes and nanopaticles was fabricated by an anodization process of the modified titanium. The local electric field at the anodized surface was simulated and its influence on the morphology of the TiO2 film was discussed. The results show that the electric field strength is enhanced by the covering. The growth rate of TiO2 increases with the assist of the local electric field. However, TiO2 dissolution is hindered since the local electric field prevents [TiF6]6- from diffusing. It means that the balance condition for the formation of nanotubes is broken, and TiO2 nanoparticles are formed. Moreover, the crystal structure of the TiO2 film was confirmed using X-ray diffraction and Raman analysis. The anatase is a main phase for the proposed film.
基金supported financially by the National Natural Science Foundation of China(Nos.51622106 and 51871049)the Fundamental Research Funds for the Central Universities(No.160708001).
文摘A layer of graphene(GR)particles was successfully deposited at the interface between Co(OH)2 nanoparticles and TiO2 nanotubes,aiming to improve the photoelectrochemical performance of the large-bandgap semiconductor TiO2.The obtained Co(OH)2/GR/TiO2 was extensively characterized by X-ray diffraction(XRD),scanning electron microscopy(SEM),transmission electron microscopy(TEM),X-ray photoelectron spectroscopy(XPS),UV–vis absorption spectra and photoluminescence(PL)emission spectra.Electrochemical impedance spectra,photogenerated potential-time(E-t),photocurrent density-time(i-t)and i-E curves and open circuit potential(OCP)curves were measured to investigate the photoelectrochemical activities and photogenerated cathodic protection properties.The results revealed that Co(OH)2/GR/TiO2 exhibits excellent photoelectrochemical and photogenerated cathodic performance due to synergistic effect between Co(OH)2 and graphene.Co(OH)2 and graphene co-modified TiO2 photoanode could provide an effective protection for 304 stainless steel(304 SS)in 3.5 wt%Na Cl solution for 12 h,which would be promising for future practical applications in the field of marine corrosion protection.
基金supported by the National Natural Science Foundation of China(Grant Nos.51672249,51802282,and 11804301)the Zhejiang Provincial Natural Science Foundation of China(Grant Nos.LQ17F040004 and LY17E020001)Fundamental Research Funds of Zhejiang Sci-Tech University(No.2019Q062)。
文摘Two-dimensional (2D) ultrathin MoS2-modified black Ti^3+-TiO2 nanotubes were fabricated using an electrospinning-hydrothermal treatment-reduction method.Bare TiO2 nanotubes were fabricated via electrospinning.Then,2D MoS2 lamellae were grown on the surface of the nanotubes and Ti^3+/Ov ions were introduced by reduction.The photocatalytic performance of the 2D MoS2/Ti^3+-TiO2 nanotubes was^15 times better than that of TiO2.The HER enhancement of the MoS2/Ti^3+-TiO2 nanotubes can be attributed to the Pt-like behavior of 2D MoS2 and the presence of Ti^3+-ions,which facilitated the quick diffusion of the photogenerated electrons to water,reducing the H2 activation barrier.The presence of Ov ions in the nanotubes and their hollow structure increased their solar utilization.
基金the National Nature Science Foundation of China(21507085,21576162)Shanghai Sailing Program of China(14YF1401500)for financial support
文摘We report the development of a novel visible response BiVO_4/TiO_2(N_2) nanotubes photoanode for photoelectrocatalytic applications. The nitrogen-treated TiO_2 nanotube shows a high carrier concentration rate, thus resulting in a high efficient charge transportation and low electron–hole recombination in the TiO_2–BiVO_4. Therefore, the BiVO_4/TiO_2(N_2) NTs photoanode enabled with a significantly enhanced photocurrent of 2.73 mA cm^(-2)(at 1 V vs. Ag/Ag Cl) and a degradation efficiency in the oxidation of dyes under visible light. Field emission scanning electron microscopy, X-ray diffractometry, energy-dispersive X-ray spectrometer, and UV–Vis absorption spectrum were conducted to characterize the photoanode and demonstrated the presence of both metal oxides as a junction composite.
文摘IrO2 and IrRuOx(Ir:Ru 60:40 at%),supported by 50 wt%onto titania nanotubes(TNTs)and(3 at%Nb)Nb-doped titania nanotubes(Nb-TNTs),as electrocatalysts for the oxygen evolution reaction(OER),were synthesized and characterized by means of structural,surface analytical and electrochemical techniques.Nb doping of titania significantly increased the surface area of the support from 145(TNTs)to 260 m2g-1(Nb-TNTs),which was significantly higher than those of the Nb-doped titania supports previously reported in the literature.The surface analytical techniques showed good dispersion of the catalysts onto the supports.The X-ray photoelectron spectroscopy analyses showed that Nb was mainly in the form of Nb(IV)species,the suitable form to behave as a donor introducing free electrons to the conduction band of titania.The redox transitions of the cyclic voltammograms,in agreement with the XPS results,were found to be reversible.Despite the supported materials presented bigger crystallite sizes than the unsupported ones,the total number of active sites of the former was also higher due to their better catalyst dispersion.Considering the outer and the total charges of the cyclic voltammograms in the range 0.1–1.4 V,stability and electrode potentials at given current densities,the preferred catalyst was Ir O2 supported on the Nb-TNTs.The electrode potentials corresponding to given current densities were between the smallest ones given in the literature despite the small oxide loading used in this work and its Nb doping,thus making the Nb-TNTs-supported IrO2 catalyst a promising candidate for the OER.The good dispersion of IrO2,high specific surface area of the Nb-doped supports,accessibility of the electroactive centers,increased stability due to Nb doping and electron donor properties of the Nb(IV)oxide species were considered the main reasons for its good performance.
基金the financial support provided by internal reseach funding of Khalifa University of Science and Technology,United Arab Emirates(Grant No.CIRA-2018-16)。
文摘Controllable synthesis of insertion-type anode materials with beneficial micro-and nanostructures is a promising approach for the synthesis of sodium-ion storage devices with high-reactivity and excellent electrochemical performance.In this study,we developed a sacrificial-templating route to synthesize TiO_(2)@N-doped carbon nanotubes(TiO_(2)@NC-NTs)with excellent electrochemical performance.The asprepared mesoporous TiO_(2)@NC-NTs with tiny nanocrystals of anatase TiO_(2) wrapped in N-doped carbon layers showed a well-defined tube structure with a large specific surface area of 198 m^(2) g^(-1) and a large pore size of~5 nm.The TiO_(2)@NC-NTs delivered high reversible capacities of 158 m A h g^(-1) at 2 C(1 C=335 m A g^(-1))for 2200 cycles and 146 m A h g^(-1) at 5 C for 4000 cycles,as well as an ultrahigh rate capability of up to 40 C with a capacity of 98 m A h g^(-1).Even at a high current density of 10 C,a capacity of 138 m A h g^(-1) could be delivered over 10,000 cycles.Thus,the synthesis of mesoporous TiO_(2)@NC-NTs was demonstrated to be an efficient approach for developing electrode materials with high sodium storage and long cycle life.
基金financially supported by the European Union via the H2020-MSCA-RISE-2016 program(BAMOS Project,734156)Royal Society via the International Exchange Program(IE161349)+2 种基金Key Research Project from the National Key Research and Development Program of China(2016YFC1100401)National Natural Science Foundation of China(51705507)Young Elite Scientists Sponsorship Program by CAST(2017QNRC0181)。
文摘TiO2 nanotubes(NT)has been demonstrated its potential in orthopaedic applications due to its enhanced surface wettability and bio-osteointegration.However,the fretting biocorrosion is the main concern that limited its successfully application in orthopaedic application.In this study,a structure optimised thin TiO2 nanotube(SONT)layer was successfully created on Ti6Al4V bone screw,and its fretting corrosion performance was investigated and compared to the pristine Ti6Al4V bone screws and NT decorated screw in a bone-screw fretting simulation rig.The results have shown that the debonding TiO2 nanotube from the bone screw reduced significantly,as a result of structure optimisation.The SONT layer also exhibited enhanced bio-corrosion resistance compared pristine bone screw and conventionally NT modified bone screw.It is postulated that interfacial layer between TiO2 nanotube and Ti6Al4V substrate,generated during structure optimisation process,enhanced bonding of TiO2 nanotube layer to the Ti6Al4V bone screws that leading to the improvement in fretting corrosion resistance.The results highlighted the potential SONT in orthopaedic application as bone fracture fixation devices.
基金financially supported by the National Key Project on Basic Research(No.2013CB933203)the Natural Science Foundation of China(Nos.21373224 and 21577143)+1 种基金the Natural Science Foundation of Fujian Province(Nos.2014H0054 and 2015J0544)the One Hundred Talents Program of the Chinese Academy of Sciences
文摘Pt-TiO2 nanotubes with tube diameter of -120 nm and uniformly dispersed Pt particles（size of -2 nm） were successfully synthesized via a carbon nanotube（CNT） templating method followed by a photo-deposition processing of Pt nanoparticles. The as-obtained Pt-TiO2 NTs possess both enhanced visible light absorption and reduced recombination of photogenerated electrons and holes. These merits boost the Pt-TiO2 NTs an excellent photocatalytic material toward photooxidation of a variety of low molecular hydrocarbons under atmospheric environment.
文摘We report the in vitro cell test and in vivo animal test results of titanium oxide nanotubes (TiO2 NTs) as a potential therapeutic agent used for cancer thermotherapy in combination with near-infrared (NIR) laser. The in vitro cell test results show that both the cells exposed to NIR laser without TiO2 NTs treatment and the cells treated with TiO2 NTs but not with NIR irradiation had cell viabilities higher than 96%. Combination of these two techniques, however, shows cell viability less than 1%. The cell death rate strongly depended on the concentration of TiO2 NTs. Also, the cell deaths were mostly due to necrosis but partly due to late apoptosis. The in vivo animal test results show that tumor cells can be completely destroyed without nearly giving damage to surrounding healthy cells by an injection of an adequate amount of TiO2 NTs/NaCl suspension and a subsequent single continuous laser treatment at a moderately low laser illumina-tion intensity for the exposure time optimized for the tumor size. These results suggest that TiO2 NTs can be effectively utilized as a therapeutic agent for cancer thermotherapy due to their excellent photothermal property and high bio-compatibility.
基金National Natural Science Foundation of China(No.11372205)
文摘A novel catalyst,TiO2 nanotubes(TiO2 NTs)composite decorated by CuO and CeO2 particles,was prepared by a simple and cost-effective method.The TiO2 NTs were fabricated by the hydrothermal method,and CuO and CeO2 particles loaded onto TiO2 NTs(CuO/CeO2@TiO2 NTs)were prepared by the water bath heating method.The CuO/CeO2@TiO2 NTs were investigated and characterized by transmission electron microscope(TEM),energy dispersive spectrometer(EDS),photoluminescence(PL),X-ray diffractometer(XRD)and ultraviolet-visible light diffuse reflectance spectrum(UV-Vis DRS).Both the p-n heterojunction formed at the p-CuO and n-TiO2 interfaces and the highly induced electron transfer of CeO2 can greatly promote the separation of electrons-holes.Therefore,CuO/CeO2@TiO2 NTs show enhanced absorption and have potential applications in photocatalysis.
基金Project supported by the National Natural Science Foundation for Joint Fund Key Project of China(Grant No.U1865206)the National Science and Technology Major Project of China(Grant No.2017-Ⅶ-0012-0107)+1 种基金the National Defense Science and Technology Key Laboratory Fund of China(Grant No.614220207011802)the Key Area Research and Development Program of Guangdong Province,China(Grant No.2019B090909002)。
文摘Nitrogen-doped TiO2 nanotubes(TNTs)were prepared by ion implantation and anodic oxidation.The prepared samples were applied in photocatalytic(PC)oxidation of methyl blue,rhodamine B,and bisphenol A under light irradiation.To explore the influence of doped ions on the band and electronic structure of TiO2,computer simulations were performed using the VASP code implementing spin-polarized density functional theory(DFT).Both substitutional and interstitial nitrogen atoms were considered.The experimental and computational results propose that the electronic structure of TiO2 was modified because of the emergence of impurity states in the band gap by introducing nitrogen into the lattice,leading to the absorption of visible light.The synergy effects of tubular structures and doped nitrogen ions were responsible for highly efficient and stable PC activities induced by visible and ultraviolet(UV)light.
基金supported by Sakarya University with Project No. BAPK-2012-50-01-018
文摘TiO2 nanotubes on Ti metal surface were prepared by the electrochemical anodization method. Then, nanosilver was deposited onto the nanotubes by the electroless dip coating and the anodization. The obtained TiO2 nanotubes were examined by using scanning electron microscopy, atomic force microscopy, Fourier transform infrared spectroscopy, X-ray diffraction, cyclic voltammetry, and UV–Vis. The electrochemical band gap（Eg^CV） of the nanosilver-coated TiO2 nanotubes prepared by the anodization was found as 1.54 eV. Using the UV–Vis measurements, the optical band gap energy（Eg^op.） was calculated as 1.51 eV for the Ag/TiO2 nanotubes obtained by electroless dip coating. The electrical conductivity of the TiO2 nanotubes also increased from 3.0 × 10^-4 to 34.7 S/cm after nano Ag deposition by the anodization method.These Ag/TiO2 nanotubes with low band gap and high electrical conductivity are desirable for the applications in electronics, Li-ion batteries, and solar cells.
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 Key R&D Program of China(2023YFA1508001)the National Natural Science Foundation of China(22272120 and U2202251)+2 种基金the Fundamental Research Funds for the Central Universities(2042022kf1174)the Hainan Province Science and Technology Special Fund(ZDYF2023SHFZ120 and ZDYF2021SHFZ058)the Research Foundation of Marine Science and Technology Collaborative Innovation Center of Hainan University(XTCX2022HYB01)。
文摘Direct utilization of co-existed ferrous oxide(FeO)dust in CO_(2)flue gas from the steel industry to product value-added materials is yet to be established.Inspired by the form of CaO-CaCO_(3)as natural carbon cycle and the high oxide dissolution capacity of molten salts,CaO is herein introduced into the affordable molten NaCl-CaCl_(2)-FeO salt to generate CO_(3)^(2-)through an efficient capture of CO_(2).The subsequent coelectrolysis of FeO and CO_(3)^(2-)successfully produces cathodic Fe-encapsulated carbon nanotubes(Fe@CNT)with enhanced energy efficiency(current efficiency of 83.1%for CO_(2)reduction and energy consumption of 22.49 kWh kg^(1)for Fe@CNT generation).The in-situ capture of CO_(2)by O^(2)generated from the electro-deoxidation of FeO bridges the electrolysis of CO_(2)and FeO,rendering the enhanced current efficiency of the co-electrolysis and template-free generation of Fe@CNT.When evaluated as functional materials for electromagnetic wave absorption,the Fe@CNT integrates dielectric loss of CNT and electromagnetic loss from Fe.The Fe well-defined in CNT induces the synergistic loss and further improves the impedance matching,resulting in excellent electromagnetic wave absorption performance.The coelectrolysis establishes a promising strategy for converting CO_(2)into highly functional materials directly from CO_(2)-containing flue gas from steel industrial without dust removal.
基金Projects(42106051,42006046,U2106206) supported by the National Natural Science Foundation of ChinaProject(22373501D) supported by Hebei Provincial Key R&D Program,China。
文摘Copper is a versatile material,commonly utilized in power transmission and electronic devices,but its relative high reactivity necessitates a long-lasting protective technique.Here,we report a method that combines plasma-enhanced non-equilibrium magnetron sputtering physical vapor deposition(PEUMS-PVD)and anodization to construct a self-healing three-dimensional Ti/Al-doped TiO_(2)nanotubes/Ti_(3)AlC_(2)coating on the surface of Cu substrates.This novel strategy enhances the corrosion resistance of copper substrates in marine environments,with corrosion current densities of up to 4.5643×10^(−8)A/cm^(2).Among them,the doping of nano-aluminum particles makes the coating self-healing.The mechanistic analysis of the corrosion behaviors during early immersion experiments was conducted using electrochemical noise,and revealed that during the initial stages of coating immersion,uniform corrosion predominates,with a minor occurrence of localized corrosion.
基金financially supported by the National Natural Science Foundation of China(Nos.52072002 and 52372037)the National Natural Science Foundation of China(No.22108003)+3 种基金the Outstanding Scientific Research and Innovation Team Program of Higher Education Institutions of Anhui Province(No.2023AH010015)the China Postdoctoral Science Foundation(No.2024M750012)the Excellent Young Talents Fund Program of Higher Education Institutions of Anhui Province(No.2023AH030026)the financial support from the Anhui International Research Center of Energy Materials Green Manufacturing and Biotechnology
文摘The size tuning of one-dimensional(1D)spatially confined electrocatalysts with abundant exposed active sites is still a huge challenge for electrocatalytic hydrogen/oxygen evolution reactions(HER/OER)and overall water splitting(OWS).Herein,we construct CoPNi_(2)P heterostructure embedded ultrafine N-doped carbon nanotubes(CoP-Ni_(2)P@U-NCNTs/NF)with a diameter size of about 50 nm from 2D cobalt-based zeolitic imidazolate framework(Co-ZIF-L/NF)via phosphorylation strategy,while Co-Ni embedded N-doped carbon nanotubes with a diameter of about 200 nm are constructed via carbonization.The size-tuned CoP-Ni_(2)P@U-NCNTs/NF possesses abundant active sites and electron transport pathways,and the stability of CoP-Ni_(2)P heterostructure is improved by carbon coating.Density functional theory(DFT)calculation results verify that the Ni_(2)P and CoP heterojunction synergistic ally promotes the electron redistribution of the Co-Ni to optimize Gibbs free energy of H*(ΔGH*).Meanwhile,the NCNTs-confined CoP-Ni_(2)P induced by phosphating accelerates the reconstruction of the CoOOH-NiOOH compared with Ni-Co,therebyboosting the reaction kinetics of efficient OWS due to the reduced reaction energy barrier of O-O coupling.As expected,the CoP-Ni_(2)P@U-NCNTs/NF favors a low overpotential of 67/203 mV@10 mA cm^(-2)for the HER/OER,realizing an ultralow cell voltage of 1.52V@10 mA cm^(-2)for OWS and long-term durability at various current densities.This work provides a feasible approach to tuning the composition and structure of highefficiency electrocatalysts for the production of green hydrogen.
基金Project(1254G024)supported by the Young Core Instructor Foundation from Heilongjiang Educational Committee,ChinaProject(2012RFQXS113)supported by Scientific and Technological Innovation Talents of Harbin,China
文摘Both Ti foil and porous Ti were anodized in 0.5%HF and in ethylene glycol electrolyte containing 0.5%NH4F(mass fraction) separately. The results show that TiO2 nanotubes can be formed on Ti foil by both processes, whereas TiO2 nanotubes can be formed on porous Ti only in the second process. The overhigh current density led to the failure of the formation nanotubes on porous Ti in 0.5%HF electrolyte. TiO2 nanotubes were characterized by SEM and XRD. TiO2 nanotubes on porous Ti were thinner than those on Ti foil. Anatase was formed when TiO2 nanotubes were annealed at 400 °C and fully turned into rutile at 700 °C. To obtain good photodegradation, the optimal heat treatment temperature of TiO2 nanotubes was 450 °C. The porosity of the substrates influenced photodegradation properties. TiO2 nanotubes on porous Ti with 60% porosity had the best photodegradation.
