To mitigate secondary electromagnetic pollution,there is an urgent need to develop absorption-dominant electromagnetic interference(EMI)shielding materials with low density,reduced thickness,lightweight construction,f...To mitigate secondary electromagnetic pollution,there is an urgent need to develop absorption-dominant electromagnetic interference(EMI)shielding materials with low density,reduced thickness,lightweight construction,flexibility,exceptional mechanical strength,and superior electrothermal and photothermal properties,particularly for flexible and wearable electronics.In this regard,we designed an absorption-based composite film comprising carbon nanotubes(CNT)and α-Fe_(2)O_(3),featuring a CNT layer sandwiched between twoα-Fe_(2)O_(3)layers on the upper and lower surfaces.This composite film was fabricated through an electrodeposition process followed by a thermal annealing procedure to achieve enhanced EMI shielding performance along with improved electrothermal and photothermal properties.The strategically designed sandwich structure allows the rough surface of the upper α-Fe_(2)O_(3)layer to not only improve the impedance mismatch between free space and the composite film,facilitating the penetration of incident electromagnetic(EM)waves into the film and promoting increased EM absorption rather than reflection,but also to enhance electrical conductivity,thereby improving electron mobility and density.Consequently,the average total shielding effectiveness(SE)of the CNT/Fe_(16)-300 composite demonstrates remarkable EMI shielding effectiveness(EMI SE:56.8 dB).Furthermore,the alteration in the absorption-to-reflection ratio(A/R)signifies a transition in the EMI shielding mechanism from reflection(0.69 for the pristine CNT film)to absorption(1.86 for the CNT/Fe_(16)-300)with the incremental deposition of α-Fe_(2)O_(3)nanoparticles.This work presents a feasible manufacturing approach for developing composite films with a sandwich structure that exhibits absorption-dominant EMI shielding capabilities,contributing to advancements in thermal management and multifunctional electromagnetic shielding applications.展开更多
Tetravalent tin(Sn4+)-based inorganic perovskite semiconductors like Cs_(2)SnI_(6)are expected to replace lead-based perovskite counterparts due to advantages such as structural stability and environmental friendlines...Tetravalent tin(Sn4+)-based inorganic perovskite semiconductors like Cs_(2)SnI_(6)are expected to replace lead-based perovskite counterparts due to advantages such as structural stability and environmental friendliness.In this paper,we reported the dopant compensation effect in the component-dependent self-doped(111)-oriented Cs_(2)SnI_(6)thin films grown with pulsed laser deposition(PLD)at room temperature.The films were grown on(100)-SrTiO_(3)(STO)substrates at room temperature by PLD.Hall results of the Cs_(2)SnI_(6)films with different components realizing by controlling the ratio of SnI_(4)/CsI in the targets demonstrate a clear change of conductivity type from N-type to P-type,while the carrier concentration decreases from 1018 to 1013 and accordingly the film resistivity increases significantly from 3.8 to 2506Ωcm.The defect-relatedopticalfingerprints of Cs_(2)SnI_(6)films werealsoinvestigated withtemperature-dependent photoluminescence spectroscopy.At low temperatures of 10 K,the Cs_(2)SnI_(6)films exhibit donor-bound(D^(0)X)and donor-acceptor pair(DAP)emission,respectively,due to the self-doping effect.These re-sults indicate that controlling the composition of the PLD target is a powerful way to tune the electrical properties of Cs_(2)SnI_(6)films for possible applications in solar cells or X-ray detectors.展开更多
In this work,flexible photothermal PVA/Ti_(2)O_(3) composite films with different amount(0 wt%,5 wt%,10 wt%,15 wt%)of Ti_(2)O_(3) particles modified by steric acid were prepared by a simple solution casting method.The...In this work,flexible photothermal PVA/Ti_(2)O_(3) composite films with different amount(0 wt%,5 wt%,10 wt%,15 wt%)of Ti_(2)O_(3) particles modified by steric acid were prepared by a simple solution casting method.The microstructures,XRD patterns,FTIR spectra,UV-Vis-NIR spectra thermo-conductivity,thermo-stability and photothermal effects of these composite films were all characterized.These results indicated that Ti_(2)O_(3) particles were well dispersed throughout the polyvinyl alcohol(PVA)matrix in the PVA/Ti_(2)O_(3) composite films.And Ti_(2)O_(3) particles could also effectively improve the photothermal properties of the composite films which exhibited high light absorption and generated a high temperature(about 57.4℃for film with 15 wt%Ti_(2)O_(3) amount)on the surface when it was irradiated by a simulated sunlight source(1 kW/m^(2)).展开更多
ZrO2/TiO2 composite photocatalytic film was produced on the pure titanium substrate using in-situ Zr(OH)4 colloidal particle by the micro-arc oxidation technique and characterized by scanning electron microscope (...ZrO2/TiO2 composite photocatalytic film was produced on the pure titanium substrate using in-situ Zr(OH)4 colloidal particle by the micro-arc oxidation technique and characterized by scanning electron microscope (SEM), energy dispersive X-ray (EDX), X-ray diffraction (XRD) and ultraviolet-visible (UV-Vis) spectrophotometer. The composite film shows a lamellar and porous structure which consists of anatase, futile and ZrO2 phases. The optical absorption edge of film is shifted to longer wavelength when ZrO2 is introduced to TiO2. Furthermore, the photocatalytic reaction rate constants of degradation of rhodamine B solution with ZrO2/TiO2 composite film and pure TiO2 film under ultraviolet irradiation are measured as 0.0442 and 0.0186 h 1, respectively.展开更多
Series of TiO 2-ZnO heterojunction composite films with different n(Zn)/n(Ti) ratios were prepared by UDP450 magnetron sputter ion plating equipment, and the mole ratio of Zn to Ti was controlled by adjusting the ...Series of TiO 2-ZnO heterojunction composite films with different n(Zn)/n(Ti) ratios were prepared by UDP450 magnetron sputter ion plating equipment, and the mole ratio of Zn to Ti was controlled by adjusting the current values of sputtering target. The effects of n(Zn)/n(Ti) on the microstructures of TiO2-ZnO films were investigated by SEM, AFM, Raman and XPS, and their photocatalytic decomposition of methyl orange solutions was evaluated. The results show that an increase in n(Zn)/n(Ti) typically results in a decrease in the grain size of composite films firstly and then an increase of grain size, while an increase in n(Zn)/n(Ti) leads to an increase in film roughness firstly and then a decrease in film roughness. Both grain size and roughness of TiO2-ZnO films reach the maximum and minimum at n(Zn)/n(Ti) of 1/9.3, respectively. The n(Zn)/n(Ti) shows little effect on the valences of Zn and Ti elements, which mainly exist in the form of TiO2 and ZnO phases. The n(Zn)/n(Ti) has influence on the amount of anatase/rutile TiO2 heterojunction in the film. With increase of the n(Zn)/n(Ti), the absorption intensity of the composite film increases and the absorption region extends to 450 nm, which is redshifted as much as 150 nm in comparison with the pure TiO2 films. However, the photocatalytic abilities of heterogeneous composite films do not depend on the n(Zn)/n(Ti) but rather on the microstructures of the TiO2-ZnO composite films. Degradation rate of the film reaches the maximum and the photocatalytic decomposition of pollutants works best when n(Zn)/n(Ti)=1:9.3.展开更多
This study focused on the development and characterization of TiO<sub>2</sub>-PES composite fibers with varying TiO<sub>2</sub> loading amounts using a phase inversion process. The resulting co...This study focused on the development and characterization of TiO<sub>2</sub>-PES composite fibers with varying TiO<sub>2</sub> loading amounts using a phase inversion process. The resulting composite fibers exhibited a sponge-like structure with embedded TiO<sub>2</sub> nanoparticles within a polymer matrix. Their photocatalytic performance for ammonia removal from aqueous solutions under UV-A light exposure was thoroughly investigated. The findings revealed that PeTi8 composite fibers displayed superior adsorption capacity compared to other samples. Moreover, the study explored the impact of pH, light intensity, and catalyst dosage on the photocatalytic degradation of ammonia. Adsorption equilibrium isotherms closely followed the Langmuir model, with the results indicating a correlation between qm values of 2.49 mg/g and the porous structure of the adsorbents. The research underscored the efficacy of TiO<sub>2</sub> composite fibers in the photocatalytic removal of aqueous under UV-A light. Notably, increasing the distance between the photocatalyst and the light source resulted in de-creased hydroxyl radical concentration, influencing photocatalytic efficiency. These findings contribute to our understanding of TiO<sub>2</sub> composite fibers as promising photocatalysts for ammonia removal in water treatment applications.展开更多
The Ni-P/TiO2 composite film on sintered NdFeB permanent magnet was investigated by X-ray diffraction (XRD),environmental scanning electron microscopy (ESEM),and energy dispersive X-ray spectrometer (EDX). The c...The Ni-P/TiO2 composite film on sintered NdFeB permanent magnet was investigated by X-ray diffraction (XRD),environmental scanning electron microscopy (ESEM),and energy dispersive X-ray spectrometer (EDX). The corrosion resistance of Ni-P/TiO2 film coated on NdFeB magnet,in 0.5 mol/L NaCl solution,was studied by potentiodynamic polarization,salt spray test and electrochemical impedance spectroscopy (EIS) techniques. The self-corrosion current density (icorr) and the polarization resistance (Rp) of Ni-P/TiO2 film are 0.22 μA/cm2 (about 14% of that of Ni-P coating),and 120 kΩ·cm2 (about 2 times of that of Ni-P coating),respectively. The anti-salt spray time of Ni-P/TiO2 film is about 2.5 times of that of the Ni-P coating. The results indicate that Ni-P/TiO2 film has a better corrosion resistance than Ni-P coating,and the composite film increases the corrosion resistance of NdFeB magnet markedly.展开更多
CuIn(S,Se)2 thin films were prepared by thermal crystallization of co-sputtered Cu-In alloy precursors in S/Se atmosphere. In-depth compositional uniformity is an important prereq- uisite for obtaining device-qualit...CuIn(S,Se)2 thin films were prepared by thermal crystallization of co-sputtered Cu-In alloy precursors in S/Se atmosphere. In-depth compositional uniformity is an important prereq- uisite for obtaining device-quality CuIn(S,Se)2 absorber thin films. In order to figure out the influence of heat treatments on in-depth composition uniformity of CuIn(S,Se)2 thin films, two kinds of reaction temperature profiles were investigated. One process is "one step profile", referring to formation of CuIn(S,Se)2 thin films just at elevated temperature (e.g. 500 ℃). The other is "two step profile", which allows for slow diffusion of S and Se elements into the alloy precursors at a low temperature before the formation and re-crystallization of CuIn(S,Se)2 thin films at higher temperature (e.g. first 250 ℃ then 500 ℃). X-ray diffrac- tion studies reveal that there is a discrepancy in the shape of (112) peak. Samples annealed with "one step profile" have splits on (112) peaks, while samples annealed with "two step profile" have relatively symmetrical (112) peaks. Grazing incident X-ray diffraction and en- ergy dispersive spectrum measurements of samples successively etched in bromine methanol show that CuIn(S,Se)2 thin films have better in-depth composition uniformity after "two step profile" annealing. The reaction mechanism during the two thermal processing was also investigated by X-ray diffraction and Raman spectra.展开更多
Cu2O/TiOa/Pt three-layer films were deposited on glass substrates using magnetron sputtering method. The surface morphology and the optical properties of the composite film were characterized by X-ray diffraction (XR...Cu2O/TiOa/Pt three-layer films were deposited on glass substrates using magnetron sputtering method. The surface morphology and the optical properties of the composite film were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), ultraviolet- visible spectroscopy (UV-Vis) and photoluminescence spectroscopy (PL). The photocatalytic activity of the samples was evaluated by the photocatalytic degradation of methyl orange (MO) aqueous solution under visible light irradiation. The results indicate that the Cu2O/TiO2/Pt composite films are made up of three layers which are Pt layer, anatase-TiO2 layer and Cu2O layer from bottom to top. The surface of the films is even and composed of regular-shaped spherical particles. The photocatalytic activity of the Cu2O/TiO2/Pt three-layer film is much higher than that of the Cu2O/TiO2 double-layer film. Such enhancement is ascribed to the presence of Pt layer, which further inhibits the photogenerated electron-hole recombination, prolongs the lifetime of the photogenerated carriers, increases the quantum efficiency and hence improves the photocatalytic activity of the film effectively.展开更多
A NiP/TiO2 composite film on carbon steel was prepared by electroless plating and sol-gel composite process. An artificial neural network was applied to optimize the prepared condition of the composite film. Corrosion...A NiP/TiO2 composite film on carbon steel was prepared by electroless plating and sol-gel composite process. An artificial neural network was applied to optimize the prepared condition of the composite film. Corrosion behavior of the NiP/TiO2 composite film was investigated by polarization resistance measurement, anode polarization, ESEM (environmental scanning electron microscopy) and EIS (electrochemical impedance spectroscopy) measurements. Results showed that the NiP/ TiO2 composite film has a good corrosion resistance in 0.5mol/L H2SO4 solution. The element valence of the composite film was characterized by XPS (X-ray photoelectron spectroscopy) spectrum, and an anticorrosion mechanism of the composite film was discussed.展开更多
A PANI/TiO2 composite film deposited on the glass surface was successfully prepared using sol-gel dip-coating technique and chemical oxidation method. The film was characterized using XRD, AFM, and UV. The result show...A PANI/TiO2 composite film deposited on the glass surface was successfully prepared using sol-gel dip-coating technique and chemical oxidation method. The film was characterized using XRD, AFM, and UV. The result showed that the TiO2 film consists of both cuboid-shaped and anatase-phased TiO2 nanoparticles. The average grain size of TiO2 in the film was approximately 20 nm. After coating with PANI, the particle was changed into irregular spherical-shaped and the size was increased up to approximately 35 nm in diameter. UV-Vis spectroscopy analysis indicated that the coating of TiO2 with PANI would result in an enhancement of photocatalytic efficiency and an extension of the photoresponse of TiO2. The band gap of the PANI/TiO2 film was 3.18 eV. The photocatalytic property of the film was evaluated by the degradation of rhodamine-B. It was found that 67.1% and 83.2% of rhodamine-B could be degraded under sunlight and UV irradiation within 120 min using the PANI/TiO2 composite t-tim as photocatalyst.展开更多
Co−TiO2 nanocomposite films were prepared via magnetron sputtering at various substrate temperatures.The films comprise Co particles dispersed in an amorphous TiO2 matrix and exhibit coexisting ferromagnetic and super...Co−TiO2 nanocomposite films were prepared via magnetron sputtering at various substrate temperatures.The films comprise Co particles dispersed in an amorphous TiO2 matrix and exhibit coexisting ferromagnetic and superparamagnetic properties.When the substrate temperature increases from room temperature to 400℃,Co particles gradually grow,and the degree of Co oxidation significantly decreases.Consequently,the saturation magnetization increases from 0.13 to 0.43 T at the same Co content by increasing the substrate temperature from room temperature to 400℃.At a high substrate temperature,conductive pathways form among some of the clustered Co particles.Thus,resistivity rapidly declines from 1600 to 76μΩ·m.The magnetoresistive characteristic of Co−TiO2 films is achieved even at resistivity of as low as 76μΩ·m.These results reveal that the obtained nanocomposite films have low Co oxidation,high magnetization and magnetoresistance at room temperature.展开更多
A novel method to fabricate composition- (IO) films using a positive sacrificial ZnO and topology-controlled ZnO/TiO2 inverse opals IO template has been developed. This method includes a two-step process, preparatio...A novel method to fabricate composition- (IO) films using a positive sacrificial ZnO and topology-controlled ZnO/TiO2 inverse opals IO template has been developed. This method includes a two-step process, preparation of ZnO IO by a simple electrochemical deposition using a self-assembly polystyrene colloidal crystal template and preparation of ZnO/TiO2 IO by a liquid phase deposition (LPD) process at room temperature. The composition and topology of ZnO/TiO2 IO can be easily controlled by changing the duration of the LPD. After 20 min LPD process, a ZnO/TiO2 composite IO with non-close-packed face-centered cubic air sphere array was obtained. Prolonging the duration to 60 min, a pure TiO2 IO (TIO-LPD60) with obviously thickened walls was formed. The formation mechanism for the compositional and topological variation was discussed. A preliminary study on UV photocatalytic property of the samples for degradation of methylene blue reveals that the composition and topology significantly influenced the photocatalytic activity of the IO film. The ZnO/TiO2 composite IO demonstrates a higher degree of activity than both pure ZnO and pure TiO2 IO, although they have a similar IO wall thickness. Moreover, with increasing IO wall thickness from -52 nm to -90 nm, TIO-LPD60 exhibits the highest level of photocatalytic performance.展开更多
Bi_(2)WO_(6) nanoplate/TiO_(2) nanowire and Bi_(2)WO_(6) nanoflower/TiO_(2) nanowire composite films were successfully prepared using a hydrothermal method.The results show that the light absorption for Bi_(2)WO_(6)/T...Bi_(2)WO_(6) nanoplate/TiO_(2) nanowire and Bi_(2)WO_(6) nanoflower/TiO_(2) nanowire composite films were successfully prepared using a hydrothermal method.The results show that the light absorption for Bi_(2)WO_(6)/TiO_(2) composite films is extended to the visible region after Bi_(2)WO_(6) nanoplates and nanoflowers are assembled onto TiO_(2) nanowires.Furthermore,Bi_(2)WO_(6) nanoflower/TiO_(2) nano wire composite film exhibits a better absorption property compared to Bi_(2)WO_(6) nanoplate/TiO_(2) nanowire film,which is mainly ascribed to the narrower bandgap of Bi_(2)WO_(6) nanoflower compared to that of Bi_(2)WO_(6) nanoplate.The photocurrent density for Bi_(2)WO_(6) nanoflower/TiO_(2) nanowire and Bi_(2)WO_(6) nanoplate/TiO_(2) nanowire composite films can reach 95 and 62.5 μA cm-2,respectively,which are much higher than that obtained for a pure TiO_(2) nanowire film(25 μA cm-2).Meanwhile,under illumination,the pure TiO_(2) nanowire,Bi_(2)WO_(6) nanoplate/TiO_(2) nanowire and Bi_(2)WO_(6) nanoflower/TiO_(2) nanowire films can reduce the potential of the coupled 304 stainless steel in 3.5 wt.%NaCl solution by 299,719 and 739 mV,respectively.Thus,Bi_(2)WO_(6) nanoflower/TiO_(2) nanowire film is found to provide the best effective photocathodic protection for 304 stainless steel.This work not only provides an example of shape-dependent photocathodic protection based on Bi_(2)WO_(6) but also opens up new possibilities to design an ideal microstructure on the basis of semiconductor materials for future applications of photocathodic protection.展开更多
TiO2 films have received increasing attention for the removal of organic pollutants via photocatalysis. To develop a simple and effective method for improving the photodegradation efficiency of pollutants in surface w...TiO2 films have received increasing attention for the removal of organic pollutants via photocatalysis. To develop a simple and effective method for improving the photodegradation efficiency of pollutants in surface water, we herein examined the preparation of a P25-TiO2 composite film on a cement substrate via a sol–gel method. In this case, Rhodamine B(Rh B)was employed as the target organic pollutant. The self-generated TiO2 film and the P25-TiO2 composite film were characterized by X-ray diffraction(XRD), N2 adsorption/desorption measurements, scanning electron microscopy(SEM), transmission electron microscopy(TEM), and diffuse reflectance spectroscopy(DRS). The photodegradation efficiencies of the two films were studied by Rh B removal in water under UV(ultraviolet) irradiation. Over 4 day exposure, the P25-TiO2 composite film exhibited higher photocatalytic performance than the self-generated TiO2 film. The photodegradation rate indicated that the efficiency of the P25-TiO2 composite film was enhanced by the addition of the rutile phase Degussa P25 powder. As such, cooperation between the anatase TiO2 and rutile P25 nanoparticles was beneficial for separation of the photo-induced electrons and holes. In addition, the influence of P25 doping on the P25-TiO2 composite films was evaluated. We found that up to a certain saturation point, increased doping enhanced the photodegradation ability of the composite film. Thus, we herein demonstrated that the doping of P25 powders is a simple but effective strategy to prepare a P25-TiO2 composite film on a cement substrate, and the resulting film exhibits excellent removal efficiency in the degradation of organic pollutants.展开更多
In this work, TiO2/Ti composite films were fabricated by 2-setp MCT and the following high temperature oxidation. Antibacterial activity of the composite films treated by ultrasonic cleaning to increase the performanc...In this work, TiO2/Ti composite films were fabricated by 2-setp MCT and the following high temperature oxidation. Antibacterial activity of the composite films treated by ultrasonic cleaning to increase the performance reliability was examined. The prepared TiO2/Ti composite films showed high photocatalytic activity in the degradation of methylene blue solution. It is obvious that? TiO2/Ti composite films have antibacterial activity under UV irradiation.展开更多
基金financially supported by the National Natural Science Foundation of China(Nos.52222202 and 51772310)Chinese Academy of Sciences Key Research Program of Frontier Sciences(No.QYZDY-SSWJSC031)Shanghai Pilot Program for Basic Research-Chinese Academy of Science,Shanghai Branch(No.JCYJ-SHFY-2021-001).
文摘To mitigate secondary electromagnetic pollution,there is an urgent need to develop absorption-dominant electromagnetic interference(EMI)shielding materials with low density,reduced thickness,lightweight construction,flexibility,exceptional mechanical strength,and superior electrothermal and photothermal properties,particularly for flexible and wearable electronics.In this regard,we designed an absorption-based composite film comprising carbon nanotubes(CNT)and α-Fe_(2)O_(3),featuring a CNT layer sandwiched between twoα-Fe_(2)O_(3)layers on the upper and lower surfaces.This composite film was fabricated through an electrodeposition process followed by a thermal annealing procedure to achieve enhanced EMI shielding performance along with improved electrothermal and photothermal properties.The strategically designed sandwich structure allows the rough surface of the upper α-Fe_(2)O_(3)layer to not only improve the impedance mismatch between free space and the composite film,facilitating the penetration of incident electromagnetic(EM)waves into the film and promoting increased EM absorption rather than reflection,but also to enhance electrical conductivity,thereby improving electron mobility and density.Consequently,the average total shielding effectiveness(SE)of the CNT/Fe_(16)-300 composite demonstrates remarkable EMI shielding effectiveness(EMI SE:56.8 dB).Furthermore,the alteration in the absorption-to-reflection ratio(A/R)signifies a transition in the EMI shielding mechanism from reflection(0.69 for the pristine CNT film)to absorption(1.86 for the CNT/Fe_(16)-300)with the incremental deposition of α-Fe_(2)O_(3)nanoparticles.This work presents a feasible manufacturing approach for developing composite films with a sandwich structure that exhibits absorption-dominant EMI shielding capabilities,contributing to advancements in thermal management and multifunctional electromagnetic shielding applications.
基金financially supported by the National Key Re-search and Development Program of China(No.2022YFC3700801)the Key R&D Program of Shandong Province,China(No.2024SFGC0102),the Jinan Bureau of Education(No.JNSX2023015)the Jinan Bureau of Science and Technology(No.202333042).
文摘Tetravalent tin(Sn4+)-based inorganic perovskite semiconductors like Cs_(2)SnI_(6)are expected to replace lead-based perovskite counterparts due to advantages such as structural stability and environmental friendliness.In this paper,we reported the dopant compensation effect in the component-dependent self-doped(111)-oriented Cs_(2)SnI_(6)thin films grown with pulsed laser deposition(PLD)at room temperature.The films were grown on(100)-SrTiO_(3)(STO)substrates at room temperature by PLD.Hall results of the Cs_(2)SnI_(6)films with different components realizing by controlling the ratio of SnI_(4)/CsI in the targets demonstrate a clear change of conductivity type from N-type to P-type,while the carrier concentration decreases from 1018 to 1013 and accordingly the film resistivity increases significantly from 3.8 to 2506Ωcm.The defect-relatedopticalfingerprints of Cs_(2)SnI_(6)films werealsoinvestigated withtemperature-dependent photoluminescence spectroscopy.At low temperatures of 10 K,the Cs_(2)SnI_(6)films exhibit donor-bound(D^(0)X)and donor-acceptor pair(DAP)emission,respectively,due to the self-doping effect.These re-sults indicate that controlling the composition of the PLD target is a powerful way to tune the electrical properties of Cs_(2)SnI_(6)films for possible applications in solar cells or X-ray detectors.
基金Funded by the Youth Backbone Teacher Training Plan in University of Henan Province(No.21220028)Science and Technology Research Project of Henan Province(No.242102321066)+2 种基金Natural Science Foundation of Henan Province(No.232300420312)Henan University of Technology Young Backbone Teacher Training Plan(No.21421260)the Innovation Training Program for College Students in Henan Province(No.202310463046)。
文摘In this work,flexible photothermal PVA/Ti_(2)O_(3) composite films with different amount(0 wt%,5 wt%,10 wt%,15 wt%)of Ti_(2)O_(3) particles modified by steric acid were prepared by a simple solution casting method.The microstructures,XRD patterns,FTIR spectra,UV-Vis-NIR spectra thermo-conductivity,thermo-stability and photothermal effects of these composite films were all characterized.These results indicated that Ti_(2)O_(3) particles were well dispersed throughout the polyvinyl alcohol(PVA)matrix in the PVA/Ti_(2)O_(3) composite films.And Ti_(2)O_(3) particles could also effectively improve the photothermal properties of the composite films which exhibited high light absorption and generated a high temperature(about 57.4℃for film with 15 wt%Ti_(2)O_(3) amount)on the surface when it was irradiated by a simulated sunlight source(1 kW/m^(2)).
基金Project(gf200901002)supported by the Open Research Fund of National Defense Key Disciplines Laboratory of Light Alloy Processing Science and Technology of Nanchang Hangkong University,China
文摘ZrO2/TiO2 composite photocatalytic film was produced on the pure titanium substrate using in-situ Zr(OH)4 colloidal particle by the micro-arc oxidation technique and characterized by scanning electron microscope (SEM), energy dispersive X-ray (EDX), X-ray diffraction (XRD) and ultraviolet-visible (UV-Vis) spectrophotometer. The composite film shows a lamellar and porous structure which consists of anatase, futile and ZrO2 phases. The optical absorption edge of film is shifted to longer wavelength when ZrO2 is introduced to TiO2. Furthermore, the photocatalytic reaction rate constants of degradation of rhodamine B solution with ZrO2/TiO2 composite film and pure TiO2 film under ultraviolet irradiation are measured as 0.0442 and 0.0186 h 1, respectively.
基金Project (2010JQ6008) supported by the Natural Science Foundation of Shaanxi Province,China
文摘Series of TiO 2-ZnO heterojunction composite films with different n(Zn)/n(Ti) ratios were prepared by UDP450 magnetron sputter ion plating equipment, and the mole ratio of Zn to Ti was controlled by adjusting the current values of sputtering target. The effects of n(Zn)/n(Ti) on the microstructures of TiO2-ZnO films were investigated by SEM, AFM, Raman and XPS, and their photocatalytic decomposition of methyl orange solutions was evaluated. The results show that an increase in n(Zn)/n(Ti) typically results in a decrease in the grain size of composite films firstly and then an increase of grain size, while an increase in n(Zn)/n(Ti) leads to an increase in film roughness firstly and then a decrease in film roughness. Both grain size and roughness of TiO2-ZnO films reach the maximum and minimum at n(Zn)/n(Ti) of 1/9.3, respectively. The n(Zn)/n(Ti) shows little effect on the valences of Zn and Ti elements, which mainly exist in the form of TiO2 and ZnO phases. The n(Zn)/n(Ti) has influence on the amount of anatase/rutile TiO2 heterojunction in the film. With increase of the n(Zn)/n(Ti), the absorption intensity of the composite film increases and the absorption region extends to 450 nm, which is redshifted as much as 150 nm in comparison with the pure TiO2 films. However, the photocatalytic abilities of heterogeneous composite films do not depend on the n(Zn)/n(Ti) but rather on the microstructures of the TiO2-ZnO composite films. Degradation rate of the film reaches the maximum and the photocatalytic decomposition of pollutants works best when n(Zn)/n(Ti)=1:9.3.
文摘This study focused on the development and characterization of TiO<sub>2</sub>-PES composite fibers with varying TiO<sub>2</sub> loading amounts using a phase inversion process. The resulting composite fibers exhibited a sponge-like structure with embedded TiO<sub>2</sub> nanoparticles within a polymer matrix. Their photocatalytic performance for ammonia removal from aqueous solutions under UV-A light exposure was thoroughly investigated. The findings revealed that PeTi8 composite fibers displayed superior adsorption capacity compared to other samples. Moreover, the study explored the impact of pH, light intensity, and catalyst dosage on the photocatalytic degradation of ammonia. Adsorption equilibrium isotherms closely followed the Langmuir model, with the results indicating a correlation between qm values of 2.49 mg/g and the porous structure of the adsorbents. The research underscored the efficacy of TiO<sub>2</sub> composite fibers in the photocatalytic removal of aqueous under UV-A light. Notably, increasing the distance between the photocatalyst and the light source resulted in de-creased hydroxyl radical concentration, influencing photocatalytic efficiency. These findings contribute to our understanding of TiO<sub>2</sub> composite fibers as promising photocatalysts for ammonia removal in water treatment applications.
基金Sponsored by Hi-Tech Research and Development Program of China (2003AA305120)
文摘The Ni-P/TiO2 composite film on sintered NdFeB permanent magnet was investigated by X-ray diffraction (XRD),environmental scanning electron microscopy (ESEM),and energy dispersive X-ray spectrometer (EDX). The corrosion resistance of Ni-P/TiO2 film coated on NdFeB magnet,in 0.5 mol/L NaCl solution,was studied by potentiodynamic polarization,salt spray test and electrochemical impedance spectroscopy (EIS) techniques. The self-corrosion current density (icorr) and the polarization resistance (Rp) of Ni-P/TiO2 film are 0.22 μA/cm2 (about 14% of that of Ni-P coating),and 120 kΩ·cm2 (about 2 times of that of Ni-P coating),respectively. The anti-salt spray time of Ni-P/TiO2 film is about 2.5 times of that of the Ni-P coating. The results indicate that Ni-P/TiO2 film has a better corrosion resistance than Ni-P coating,and the composite film increases the corrosion resistance of NdFeB magnet markedly.
文摘CuIn(S,Se)2 thin films were prepared by thermal crystallization of co-sputtered Cu-In alloy precursors in S/Se atmosphere. In-depth compositional uniformity is an important prereq- uisite for obtaining device-quality CuIn(S,Se)2 absorber thin films. In order to figure out the influence of heat treatments on in-depth composition uniformity of CuIn(S,Se)2 thin films, two kinds of reaction temperature profiles were investigated. One process is "one step profile", referring to formation of CuIn(S,Se)2 thin films just at elevated temperature (e.g. 500 ℃). The other is "two step profile", which allows for slow diffusion of S and Se elements into the alloy precursors at a low temperature before the formation and re-crystallization of CuIn(S,Se)2 thin films at higher temperature (e.g. first 250 ℃ then 500 ℃). X-ray diffrac- tion studies reveal that there is a discrepancy in the shape of (112) peak. Samples annealed with "one step profile" have splits on (112) peaks, while samples annealed with "two step profile" have relatively symmetrical (112) peaks. Grazing incident X-ray diffraction and en- ergy dispersive spectrum measurements of samples successively etched in bromine methanol show that CuIn(S,Se)2 thin films have better in-depth composition uniformity after "two step profile" annealing. The reaction mechanism during the two thermal processing was also investigated by X-ray diffraction and Raman spectra.
基金financially supported by the National Natural Science Foundation of China (No.51301118)the Projects of International Cooperation in Shanxi (No.2014081002)the Scientific and Technological Innovation Programs of Higher Education Institutions in Shanxi (No.2013108)
文摘Cu2O/TiOa/Pt three-layer films were deposited on glass substrates using magnetron sputtering method. The surface morphology and the optical properties of the composite film were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), ultraviolet- visible spectroscopy (UV-Vis) and photoluminescence spectroscopy (PL). The photocatalytic activity of the samples was evaluated by the photocatalytic degradation of methyl orange (MO) aqueous solution under visible light irradiation. The results indicate that the Cu2O/TiO2/Pt composite films are made up of three layers which are Pt layer, anatase-TiO2 layer and Cu2O layer from bottom to top. The surface of the films is even and composed of regular-shaped spherical particles. The photocatalytic activity of the Cu2O/TiO2/Pt three-layer film is much higher than that of the Cu2O/TiO2 double-layer film. Such enhancement is ascribed to the presence of Pt layer, which further inhibits the photogenerated electron-hole recombination, prolongs the lifetime of the photogenerated carriers, increases the quantum efficiency and hence improves the photocatalytic activity of the film effectively.
文摘A NiP/TiO2 composite film on carbon steel was prepared by electroless plating and sol-gel composite process. An artificial neural network was applied to optimize the prepared condition of the composite film. Corrosion behavior of the NiP/TiO2 composite film was investigated by polarization resistance measurement, anode polarization, ESEM (environmental scanning electron microscopy) and EIS (electrochemical impedance spectroscopy) measurements. Results showed that the NiP/ TiO2 composite film has a good corrosion resistance in 0.5mol/L H2SO4 solution. The element valence of the composite film was characterized by XPS (X-ray photoelectron spectroscopy) spectrum, and an anticorrosion mechanism of the composite film was discussed.
基金This work was financially supported by the Combined Project between the Educational Commission and the Economic Commission of Gansu Province (Nos. 99CX-04, 0310B-08)the Natural Science Foundation of Gansu Province (No. 3ZS041-A25-028)the Invention Project of Science & Technology (No. KJCXGC-01, NWNU), China.
文摘A PANI/TiO2 composite film deposited on the glass surface was successfully prepared using sol-gel dip-coating technique and chemical oxidation method. The film was characterized using XRD, AFM, and UV. The result showed that the TiO2 film consists of both cuboid-shaped and anatase-phased TiO2 nanoparticles. The average grain size of TiO2 in the film was approximately 20 nm. After coating with PANI, the particle was changed into irregular spherical-shaped and the size was increased up to approximately 35 nm in diameter. UV-Vis spectroscopy analysis indicated that the coating of TiO2 with PANI would result in an enhancement of photocatalytic efficiency and an extension of the photoresponse of TiO2. The band gap of the PANI/TiO2 film was 3.18 eV. The photocatalytic property of the film was evaluated by the degradation of rhodamine-B. It was found that 67.1% and 83.2% of rhodamine-B could be degraded under sunlight and UV irradiation within 120 min using the PANI/TiO2 composite t-tim as photocatalyst.
基金Project(2016YFE0205700)supported by the National Key Research and Development Program of ChinaProject(18JCYBJC18000)supported by the Natural Science Foundation of Tianjin City,China。
文摘Co−TiO2 nanocomposite films were prepared via magnetron sputtering at various substrate temperatures.The films comprise Co particles dispersed in an amorphous TiO2 matrix and exhibit coexisting ferromagnetic and superparamagnetic properties.When the substrate temperature increases from room temperature to 400℃,Co particles gradually grow,and the degree of Co oxidation significantly decreases.Consequently,the saturation magnetization increases from 0.13 to 0.43 T at the same Co content by increasing the substrate temperature from room temperature to 400℃.At a high substrate temperature,conductive pathways form among some of the clustered Co particles.Thus,resistivity rapidly declines from 1600 to 76μΩ·m.The magnetoresistive characteristic of Co−TiO2 films is achieved even at resistivity of as low as 76μΩ·m.These results reveal that the obtained nanocomposite films have low Co oxidation,high magnetization and magnetoresistance at room temperature.
文摘A novel method to fabricate composition- (IO) films using a positive sacrificial ZnO and topology-controlled ZnO/TiO2 inverse opals IO template has been developed. This method includes a two-step process, preparation of ZnO IO by a simple electrochemical deposition using a self-assembly polystyrene colloidal crystal template and preparation of ZnO/TiO2 IO by a liquid phase deposition (LPD) process at room temperature. The composition and topology of ZnO/TiO2 IO can be easily controlled by changing the duration of the LPD. After 20 min LPD process, a ZnO/TiO2 composite IO with non-close-packed face-centered cubic air sphere array was obtained. Prolonging the duration to 60 min, a pure TiO2 IO (TIO-LPD60) with obviously thickened walls was formed. The formation mechanism for the compositional and topological variation was discussed. A preliminary study on UV photocatalytic property of the samples for degradation of methylene blue reveals that the composition and topology significantly influenced the photocatalytic activity of the IO film. The ZnO/TiO2 composite IO demonstrates a higher degree of activity than both pure ZnO and pure TiO2 IO, although they have a similar IO wall thickness. Moreover, with increasing IO wall thickness from -52 nm to -90 nm, TIO-LPD60 exhibits the highest level of photocatalytic performance.
基金supported by the National Natural Science Foundation of China(Nos.51822402,51671044 and 52001051)the National Key Research and Development Program of China(Nos.2019YFA0209901 and 2018YFA0702901)+4 种基金the fund of the State Key Laboratory of Solidification Processing in NWPU(Grant No.SKLSP201902)the Liao Ning Revitalization Talents Program(XLYC1807047)the National MCF Energy R&D Program(No.2018YFE0312400)the Fund of Science and Technology on Reactor Fuel and Materials Laboratory(STRFML-2020-04)the China Postdoctoral Science Foundation(No.2020M670747).
文摘Bi_(2)WO_(6) nanoplate/TiO_(2) nanowire and Bi_(2)WO_(6) nanoflower/TiO_(2) nanowire composite films were successfully prepared using a hydrothermal method.The results show that the light absorption for Bi_(2)WO_(6)/TiO_(2) composite films is extended to the visible region after Bi_(2)WO_(6) nanoplates and nanoflowers are assembled onto TiO_(2) nanowires.Furthermore,Bi_(2)WO_(6) nanoflower/TiO_(2) nano wire composite film exhibits a better absorption property compared to Bi_(2)WO_(6) nanoplate/TiO_(2) nanowire film,which is mainly ascribed to the narrower bandgap of Bi_(2)WO_(6) nanoflower compared to that of Bi_(2)WO_(6) nanoplate.The photocurrent density for Bi_(2)WO_(6) nanoflower/TiO_(2) nanowire and Bi_(2)WO_(6) nanoplate/TiO_(2) nanowire composite films can reach 95 and 62.5 μA cm-2,respectively,which are much higher than that obtained for a pure TiO_(2) nanowire film(25 μA cm-2).Meanwhile,under illumination,the pure TiO_(2) nanowire,Bi_(2)WO_(6) nanoplate/TiO_(2) nanowire and Bi_(2)WO_(6) nanoflower/TiO_(2) nanowire films can reduce the potential of the coupled 304 stainless steel in 3.5 wt.%NaCl solution by 299,719 and 739 mV,respectively.Thus,Bi_(2)WO_(6) nanoflower/TiO_(2) nanowire film is found to provide the best effective photocathodic protection for 304 stainless steel.This work not only provides an example of shape-dependent photocathodic protection based on Bi_(2)WO_(6) but also opens up new possibilities to design an ideal microstructure on the basis of semiconductor materials for future applications of photocathodic protection.
基金supported by the National Science Funds for Creative Research Groups of China (No. 51421006)the National Major Projects of Water Pollution Control and Management Technology (No. 2017ZX07204003)+2 种基金the National Key Plan for Research and Development of China (2016YFC0502203)the Key Program of National Natural Science Foundation of China (No. 91647206)the Qing Lan Project of Jiangsu Province, and PAPD
文摘TiO2 films have received increasing attention for the removal of organic pollutants via photocatalysis. To develop a simple and effective method for improving the photodegradation efficiency of pollutants in surface water, we herein examined the preparation of a P25-TiO2 composite film on a cement substrate via a sol–gel method. In this case, Rhodamine B(Rh B)was employed as the target organic pollutant. The self-generated TiO2 film and the P25-TiO2 composite film were characterized by X-ray diffraction(XRD), N2 adsorption/desorption measurements, scanning electron microscopy(SEM), transmission electron microscopy(TEM), and diffuse reflectance spectroscopy(DRS). The photodegradation efficiencies of the two films were studied by Rh B removal in water under UV(ultraviolet) irradiation. Over 4 day exposure, the P25-TiO2 composite film exhibited higher photocatalytic performance than the self-generated TiO2 film. The photodegradation rate indicated that the efficiency of the P25-TiO2 composite film was enhanced by the addition of the rutile phase Degussa P25 powder. As such, cooperation between the anatase TiO2 and rutile P25 nanoparticles was beneficial for separation of the photo-induced electrons and holes. In addition, the influence of P25 doping on the P25-TiO2 composite films was evaluated. We found that up to a certain saturation point, increased doping enhanced the photodegradation ability of the composite film. Thus, we herein demonstrated that the doping of P25 powders is a simple but effective strategy to prepare a P25-TiO2 composite film on a cement substrate, and the resulting film exhibits excellent removal efficiency in the degradation of organic pollutants.
文摘In this work, TiO2/Ti composite films were fabricated by 2-setp MCT and the following high temperature oxidation. Antibacterial activity of the composite films treated by ultrasonic cleaning to increase the performance reliability was examined. The prepared TiO2/Ti composite films showed high photocatalytic activity in the degradation of methylene blue solution. It is obvious that? TiO2/Ti composite films have antibacterial activity under UV irradiation.