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Enhancing photocatalytic CO2reduction with Z-scheme heterojunction Ag/Bi2MoO6/BiOBr composite films:Synthesis and mechanistic insights 认领 引用
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作者 LI Jiao ZHAO Jing +3 位作者 WANG Yiming ZHAO Wenhai CHAI Yizhuo ZHANG Xiaochao 《燃料化学学报(中英文)》 EI CAS CSCD 北大核心 2026年第4期140-150,共11页
This study presents the successful synthesis of a novel Z-scheme heterojunction composite film consisting of Ag/Bi2MoO6/BiOBr through electrochemical processes and ionexchange techniques,followed by the photodep... This study presents the successful synthesis of a novel Z-scheme heterojunction composite film consisting of Ag/Bi2MoO6/BiOBr through electrochemical processes and ionexchange techniques,followed by the photodeposition of noble metal silver(Ag)onto the composite structure.The catalytic efficiency of semiconductor photocatalysts is greatly improved by utilizing the localized surface plasmon resonance(LSPR)effect observed in Ag nanoparticles(NPs).Furthermore,the noble metal Ag serves as an intermediary bridge facilitating charge transfer between Bi2MoO6and BiOBr,while the formation of a Schottky barrier effectively inhibits the recombination of photo-generated electron-hole pairs.As a result,the Ag-deposited Bi2MoO6/BiOBr film exhibits superior photocatalytic performance in the reduction of CO2compared to its unmodified counterpart.Our experimental results indicate a non-linear relationship between Ag deposition and the efficiency of photocatalytic CO2reduction to CO,characterized by an initial increase in efficiency followed by a decline.The optimized 1.5%-Ag/Bi2MoO6/BiOBr film demonstrates exceptional photocatalytic activity,attaining a CO production rate of 13.65μmol/(g·h).This research explores the fundamental mechanisms that lead to improved photocatalytic CO2reduction capabilities of the Ag/Bi2MoO6/BiOBr film.Our research offers important perspectives for the thoughtful design and production of highly efficient photocatalysts,which are essential for advancing sustainable energy solutions. 展开更多
关键词 photocatalytic CO2reduction Ag NPs Bi2MoO6/BiOBr composite film Z-scheme heterojunction in situ synthesis
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Flexible, magnetic and sandwich-structural Fe2O3/CNT/Fe2O3 composite film with absorption-dominant EMI shielding performance 认领 引用 被引量:4
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作者 Mengmeng Wang Li Tian +4 位作者 Xiao You Junmin Zhang Qinggang Li Jinshan Yang Shaoming Dong 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2025年第24期122-132,共11页
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-Fe2O3,featuring a CNT layer sandwiched between twoα-Fe2O3layers 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-Fe2O3layer 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/Fe16-300 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/Fe16-300)with the incremental deposition of α-Fe2O3nanoparticles.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
关键词 Absorption-dominant electromagnetic interference CNT/Fe16-300 composite film Sandwich structure α-Fe2O3layer
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Scalable Synthesis of Ultrathin Silica Nanosheets for Applications in Thermal-Management Aerogels and Flexible Composite Films 认领 引用
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作者 Qun-Yao Yuan Yuan-Fan Gu +1 位作者 Rong-Rong Cheacharoen Jie Zhao 《Rare Metals》 SCIE EI CAS CSCD 2026年第1期569-579,共11页
Silica nanosheets(SiO2 NSs) hold great promise for advanced thermal protection applications because of their exceptional thermal and chemical stability.However,their development has been hindered by challenges in s... Silica nanosheets(SiO2 NSs) hold great promise for advanced thermal protection applications because of their exceptional thermal and chemical stability.However,their development has been hindered by challenges in scalable synthesis and structural integration for specialized applications.Herein,we report a facile and scalable wet-chemical strategy for producing high-quality and ultrathin SiO2 NSs with lateral dimension more than 5 μm and thickness of ~2 nm.After graphene oxide(GO)-templated thermal treatment,the mechanical stiffness of the SiO2 NSs was significantly enhanced from 60.9 to 76.1 GPa.Leveraging their unique ultrathin and large lateral properties,the ultralight SiO2 NSs aerogel was achieved via a bidirectional freeze-casting technique.The aerogel demonstrates excellent fire resistance and high-temperature tolerance,maintaining its structure upon direct exposure to 1200℃ flames.Furthermore,the integration of SiO2 NSs into a polycaprolactone(PCL) matrix has enabled the development of a large-area and flexible fire-retardant composite film,which exhibits an exceptional flame selfextinguishing time of 2 s and mechanical flexibility.This work offers a scalable platform for fabricating functional SiO2 NSsbased materials and paves the way for their potential application in energy devices,aerospace protection,and flexible electronics. 展开更多
关键词 SiO2aerogels SiO2composite films SiO2nanosheets thermal management
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Corrosion Resistance of Sintered NdFeB Permanent Magnet With Ni-P/TiO_2 Composite Film 认领 引用 被引量:20
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作者 SONG Lai-zhou YANG Zhi-yong 《Journal of Iron and Steel Research International》 SCIE CAS 2009年第3期89-94,共6页
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
关键词 sintered NdFeB permanent magnet Ni-P/TiO2 composite film sodium chloride solution corrosion resistance
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The effects of radiation damage on power VDMOS devices with composite SiO_2-Si_3N_4 films 认领 引用 被引量:3
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作者 高博 刘刚 +5 位作者 王立新 韩郑生 宋李梅 张彦飞 腾瑞 吴海舟 《Chinese Physics B》 SCIE EI CAS CSCD 2013年第3期393-398,共6页
Total dose effects and single event effects on radiation-hardened power vertical double-diffusion metal oxide semiconductor(VDMOS) devices with composite SiO2-Si3N4 film gates are investigated.The relationships amon... Total dose effects and single event effects on radiation-hardened power vertical double-diffusion metal oxide semiconductor(VDMOS) devices with composite SiO2-Si3N4 film gates are investigated.The relationships among the important electrical parameters of the samples with different thickness SiO2-Si3N4 films,such as threshold voltage,breakdown voltage,and on-state resistance in accumulated dose,are discussed.The total dose experiment results show that the breakdown voltage and the on-state resistance barely change with the accumulated dose.However,the relationships between the threshold voltages of the samples and the accumulated dose are more complex,and not only positively drift,but also negatively drift.At the end of the total dose experiment,we select the group of samples which have the smaller threshold voltage shift to carry out the single event effect studies.We find that the samples with appropriate thickness ratio SiO2-Si3N4 films have a good radiation-hardening ability.This method may be useful in solving both the SEGR and the total dose problems with the composite SiO2-Si3N4 films. 展开更多
关键词 power VDMOS device total dose effects single event effects composite SiO2-Si3N4 films
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PREPARATION AND CORROSION RESISTANCE OF NiP/TiO_2 COMPOSITE FILM ON CARBON STEEL IN SULFURIC ACID SOLUTION 认领 引用 被引量:5
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作者 L.Z. Song S.Z. Song J. Zhao 《Acta Metallurgica Sinica(English Letters)》 EI CAS 2006年第2期117-123,共7页
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
关键词 electroless plating and sol-gel composite process artificial neural network NiP/TiO2 composite film corrosion resistance
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DEFORMATION INVESTIGATION ON iPP/SiO_2 COMPOSITES: INFLUENCE OF STRETCHING TEMPERATURE AND PARTICLE SIZE ON MORPHOLOGY EVOLUTION AND CRYSTALLINE STRUCTURE OF THIN FILMS 认领 引用
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作者 Xiu-qin Zhang Qian Xing +2 位作者 Rong-bo Li 王锐 Du-jin Wang 《Chinese Journal of Polymer Science》 SCIE EI CAS CSCD 2013年第2期275-284,共10页
In the present work, structure changes during (SiO2) composites have been investigated systematically stretching of isotactic polypropylene (iPP) and iPP/silicon dioxide The or-form crystal structure of both iPP a... In the present work, structure changes during (SiO2) composites have been investigated systematically stretching of isotactic polypropylene (iPP) and iPP/silicon dioxide The or-form crystal structure of both iPP and iPP/SiO2 composites is destroyed and transforms into the mesophase as the samples are stretched at a low temperature (35℃), while stretching at high temperatures (90℃ and 120℃) can restrain the appearance of defects and keep the perfection of crystal structure. FTIR results reveal that the stretching temperatures show no obvious difference of the effect on the orientation of pure iPP, however, the orientation of iPP/SiO2 composites is greatly changed by the tensile temperature. In the case of micron-sized SiO2 particles (average particle diameter d 〉 1 μm), the orientation of the composites is lower than that of pure iPP at all stretching temperatures. The above results suggest that the stretching temperature and the SiO2 particle size have great influence on the structure variation and orientation behavior of iPP/SiO2 composites. 展开更多
关键词 iPP/SiO2 composites Stretching Morphology Structure variation.
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Enhanced nonlinear optical absorption of Au/SiO_2 nano-composite thin films 认领 引用
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作者 赵翠华 张波萍 尚鹏鹏 《Chinese Physics B》 SCIE EI CAS 2009年第12期5539-5543,共5页
Nano metal-particle dispersed glasses are the attractive candidates for nonlinear optical material applications. Au/SiO2 nano-composite thin films with 3 vol% to 65 vol% Au are prepared by inductively coupled plasma s... Nano metal-particle dispersed glasses are the attractive candidates for nonlinear optical material applications. Au/SiO2 nano-composite thin films with 3 vol% to 65 vol% Au are prepared by inductively coupled plasma sputtering. Au particles as perfect spheres with diameters between 10 nm and 30 nm are uniformly dispersed in the SiO2 matrix. Optical absorption peaks due to the surface plasmon resonance of Au particles are observed. The absorption property is enhanced with the increase of Au content, showing a maximum value in the films with 37 vol% Au. The absorption curves of the Au/SiO2 thin films with 3 vol% to 37 vol% Au accord well with the theoretical optical absorption spectra obtained from Mie resonance theory. Increasing Au content over 37 vol% results in the partial connection of Au particles, whereby the intensity of the absorption peak is weakened and ultimately replaced by the optical absorption of the bulk. The band gap decreases with Au content increasing from 3 vol% to 37 vol % but increases as Au content further increases. 展开更多
关键词 Au/SiO2 nano-composite film plasma sputtering optical absorption spectra
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Preparation and characterization of ZrO_2/TiO_2 composite photocatalytic film by micro-arc oxidation 认领 引用 被引量:9
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作者 罗强 蔡启舟 +4 位作者 李欣蔚 潘振华 李玉洁 陈喜娣 严青松 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2013年第10期2945-2950,共6页
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
关键词 pure titanium micro-arc oxidation Zr(OH)4 colloidal particle ZrO2/TiO2 composite photocatalytic film
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Ultrafast laser dynamics of metal organic frameworks/TiO_2 nano-arrays hybrid composites for energy conversion applications 认领 引用 被引量:3
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作者 Fatma M.Ismail Daniel O'Neil +1 位作者 Tareq Youssef Souad A.Elfeky 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2019年第2期88-94,共7页
Herein,we report the victorious synthesis of metal-organic frameworks(MOFs) on TiO_2 nanotubes(NTs)using a layer-by-layer(LbL) approach.Highly crystalline and homogenous thin films of MOFs were grown and characterized... Herein,we report the victorious synthesis of metal-organic frameworks(MOFs) on TiO_2 nanotubes(NTs)using a layer-by-layer(LbL) approach.Highly crystalline and homogenous thin films of MOFs were grown and characterized using XRD,SEM,FT-IR and UV/Vis spectroscopy.Moreover,the utilization of the MOF films as sensitizers was probed in bespoke Graetzel type liquid junction solar cells.The constructed cell performance revealed an Isc of 1.16 mA cm–2,Vocof 0.63 V,FF of 0.33,and Eff of 0.42%.Further,pumpprobe transient laser spectroscopy was performed to investigate the energy and charge transfer dynamics of the MOFs/TiO_2 NTs interface.The results indicated 86% injection efficiency.The ultrafast pump-probe spectroscopy allows the investigation of this process and the differences between MOFs.It also showed that the relaxation of the MOF chromophores is in competition with electron injection in the Ti O2 motif.Thus this study provides a new insight into electron transfer from photoexcited metal-organic frameworks(MOFs) into titanium dioxide. 展开更多
关键词 Ultrafast laser dynamics Metal-organic frameworks TiO2 nano-arrays Energy conversion Thin film
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Grain Size and Wettability of TiO_2/SiO_2 Photocatalytic Composite Thin Filing 认领 引用 被引量:12
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作者 Jiaguo Yu, Xiujian Zhao, Jimmy C Yu, Jun Lin (State Key Laboratory of Advanced Technology for Materials Synthesis and Processing, Wuhan University of Technology, Wuhan 430070, China Deportment of Chemised The Chinese University of Hong Kong, Hong Kong, 《Rare Metals》 SCIE EI CAS 2001年第2期81-86,共6页
The uniform transparent TiO2/SiO2 photocatalytic composite thin films are prepared by sol-gel method on the soda lime glass substrates, and characterized by UV-visible spectroscopy, X-ray diffraction (XRD), transmissi... The uniform transparent TiO2/SiO2 photocatalytic composite thin films are prepared by sol-gel method on the soda lime glass substrates, and characterized by UV-visible spectroscopy, X-ray diffraction (XRD), transmission electron microscopy (TEM), BET surface area, FTIR spectroscopy and X-ray photoelectron spectroscopy (XPS). It was found that the addition of SiO2 to TiO2 thin films can suppress the grain growth of TiO2 crystal, increase the hydroxyl content on the surface of TiO2 films, lower the contact angle for water on TiO, films and enhance the hydrophilic property of TiO2 films. The super-hydrophilic TiO2/SiO2 photocatalytic composite thin films with the contact angle of 0((o) under bar) are obtained by the addition of 10%-20% SiO2 in mole fraction. 展开更多
关键词 sol-gel method TiO2/SiO2 photocatalytic composite thin films grain size wettability
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The influence of ablation products on the ablation resistance of C/C-SiC composites and the growth mechanism of SiO_2 nanowires 认领 引用 被引量:2
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作者 李县辉 燕青芝 +3 位作者 米应映 韩永军 温馨 葛昌纯 《Chinese Physics B》 SCIE EI CAS CSCD 2015年第2期7-11,共5页
Ablation under oxyacetylene torch with heat flux of 4186.8(10%kW/m2 for 20 s was performed to evaluate the ablation resistance of C/C-SiC composites fabricated by chemical vapor infiltration(CVI) combined with liqu... Ablation under oxyacetylene torch with heat flux of 4186.8(10%kW/m2 for 20 s was performed to evaluate the ablation resistance of C/C-SiC composites fabricated by chemical vapor infiltration(CVI) combined with liquid silicon infiltration(LSI) process.The results indicated that C/C-SiC composites present a better ablation resistance than C/C composites without doped SiC.The doped SiC and the ablation products SiO2 derived from it play key roles in ablation process.Bulk quantities of SiO2 nanowires with diameter of 80 nm-150 nm and length of tens microns were observed on the surface of specimens after ablation.The growth mechanism of the SiO_2 nanowires was interpreted with a developed vapor-liquid-solid(VLS) driven by the temperature gradient. 展开更多
关键词 C/C-SiC composites ablation products SiO2 nanowires growth mechanism
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Preparation of NaYF_4:Er3+/TiO_2 composite and up-conversion luminescence properties under visible light excitation 认领 引用 被引量:3
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作者 叶岩溪 胡晓云 +6 位作者 闫志云 刘恩周 樊君 张德恺 苗慧 商毅博 杨娟 《Chinese Physics B》 SCIE EI CAS CSCD 2011年第8期449-453,共5页
The up-conversion luminescence composite NaYF4:Er3+/TiO2 is prepared using the sol-gel method. The specimen has good crystallinity and two shapes, i.e., viereck and round, while the sizes of viereck and round partic... The up-conversion luminescence composite NaYF4:Er3+/TiO2 is prepared using the sol-gel method. The specimen has good crystallinity and two shapes, i.e., viereck and round, while the sizes of viereck and round particles are both micron-sized. The TiO2 has an anatase structure, while the NaYF4 has a hexagonal phase, which can be hardly obtained through the common sol-gel method. Due to the big particle size and the high crystallinity of pure NaYF4: Er3+, the composite has a small specific surface area that is less than Degussa P25 TiO2. The NaYF4:Er3+/TiO2 composite shows several emission peaks at 211, 237, and 251 nm under the excitation of 388 nm, at 395 nm and 411 nm under the excitation of 500 nm, and at 467, 481,492, and 508 nm under the excitation of 570 nm. 展开更多
关键词 ~p-conversion luminescence NaYF4:Er3+/TiO2 composite excitation of visible light
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Effect of Zn and Ti mole ratio on microstructure and photocatalytic properties of magnetron sputtered TiO_2-ZnO heterogeneous composite film 认领 引用 被引量:2
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作者 白力静 寇钢 +1 位作者 龚振瑶 赵志明 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2013年第12期3643-3649,共7页
Series of TiO 2-ZnO heterojunction composite films with different n(Zn)(Ti) ratios were prepared by UDP450 magnetron sputter ion plating equipment, and the mole ratio of Zn to Ti was controlled by adjusting the cu... Series of TiO 2-ZnO heterojunction composite films with different n(Zn)(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)(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)(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)(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)(Ti) of 1/9.3, respectively. The n(Zn)(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)(Ti) has influence on the amount of anataseutile TiO2 heterojunction in the film. With increase of the n(Zn)(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)(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)(Ti)=1:9.3. 展开更多
关键词 magnetron sputtering TiO2-ZnO thin films Zn to Ti mole ratio microstructure photocatalytic
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Substrate temperature dependence of chemical state and magnetoresistance characteristics of Co–TiO2 nanocomposite films 认领 引用 被引量:1
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作者 Hao-yu CHEN Yi-wen ZHANG +3 位作者 Zhong WU Zhen-bo QIN Shan-shan WU Wen-bin HU 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2020年第9期2502-2509,共8页
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
关键词 Co TiO2 nanocomposite films ferromagnetic property superparamagnetic property magnetoresistance
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Construction of SiO2-TiO2/g-C3N4 composite photocatalyst for hydrogen production and pollutant degradation: Insight into the effect of SiO2 认领 引用 被引量:1
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作者 Sijia Sun Hao Ding +5 位作者 Lefu Mei Ying Chen Qiang Hao Wanting Chen Zhuoqun Xu Daimei Chen 《Chinese Chemical Letters》 SCIE CAS CSCD 2020年第9期2287-2294,共8页
Using low-cost precipitated silica(SiO2) as the carrier,a ternary SiO2-TiO2/g-C3N4 composite photocatalyst was prepared via the sol-gel method associated with a wet-grinding process.The asprepared composite exhibits p... Using low-cost precipitated silica(SiO2) as the carrier,a ternary SiO2-TiO2/g-C3N4 composite photocatalyst was prepared via the sol-gel method associated with a wet-grinding process.The asprepared composite exhibits photocatalytic hydrogen production and pollutant degradation performance under solar-like irradiation.The effect of SiO2 carrier on the properties of the heterostructure between TiO2 and g-C3N4(CN) was systematically studied.It is found that SiO2 has important effects on promoting the interaction between TiO2 and CN.The particle size of TiO2 and CN was obviously reduced during the calcination process due to the effects of SiO2.Especially,the TiO2 particles exhibit monodispersed state with particle size below 10 nm(quantum dots),resulting in the improvement of the contact area and the interaction betweenTiO2 and CN,and leading to the formation of efficient TiO2/CN Zscheme heterostructure in SiO2-TiO2/CN.Besides,the introduction of SiO2 can increase the specific surface area and light absorption of SiO2-TiO2/CN,further promoting the photocatalytic reaction.As expected,the optimum SiO2-TiO2/CN composite exhibits 12.3,3.1 and 2.9 times higher photocatalytic hydrogen production rate than that of SiO2-TiO2,CN and TiO2/CN under solar-like irradiation,while the photocatalytic active component in SiO2-TiO2/CN is only about 60 wt%.Moreover,the rhodamine B degradation rate of SiO2-TiO2/CN is also higher than that of SiO2-TiO2,CN and TiO2/CN. 展开更多
关键词 SiO2 carrier Heterostructure Photocatalyst g-C3N4 TiO2
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Effect of catalyst on structure of(PEO)_8LiClO_4-SiO_2 composite polymer electrolyte films 认领 引用 被引量:3
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作者 潘春跃 张倩 +2 位作者 冯庆 高金环 赵悠曼 《Journal of Central South University of Technology》 2008年第4期438-442,共5页
(PEO)8LiClO4-SiO2 composite polymer electrolytes(CPEs)were prepared by in-situ reaction,in which ethyl-orthosilicate(TEOS)was catalyzed by HCl and NH3.H2O,respectively.The ionic conductivity,the contact angle and the ... (PEO)8LiClO4-SiO2 composite polymer electrolytes(CPEs)were prepared by in-situ reaction,in which ethyl-orthosilicate(TEOS)was catalyzed by HCl and NH3.H2O,respectively.The ionic conductivity,the contact angle and the morphology of inorganic particles in the CPEs were investigated by AC impedance spectra,contact angle method and TEM.The conductivities of acid-catalyzed CPE and alkali-catalyzed CPE are 2.2×10-5and 1.1×10-5S/cm respectively at 30℃.The results imply that the catalyst plays an important role in the structure of in-situ preparation of SiO2,and influences the surface energy and conductivity of CPE films directly.Meanwhile,the ionic conductivity is related to the surface energy. 展开更多
关键词 PEO(polyethylene oxide) SiO2 composite polymer electrolyte conductivity catalytic reaction
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Fracture Mechanism of 3D, Five-directional Braided (SiO_2)_f /SiO_2 Composites Prepared by Silicasol-infiltration-sintering Method 认领 引用 被引量:1
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作者 李斌斌 ZHU Jianxun +2 位作者 LIN Long LIU Yong CHEN Zhaofeng 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2013年第2期355-357,共3页
Three-dimensional (3D) five-directional braided (SiO2)/SiO2 composites were prepared by silicasol-infiltration-sintering (SIS) method. The flexural properties and microstructures were studied. The flexural stren... Three-dimensional (3D) five-directional braided (SiO2)/SiO2 composites were prepared by silicasol-infiltration-sintering (SIS) method. The flexural properties and microstructures were studied. The flexural strength and flexural elastic modulus were found to be 73 MPa and 12 GPa, respectively. The results of stress vs deflection curve and SEM examinations revealed that the fracture mechanism of 3D, five-directional braided (SiO2)/SiO2 composite was a mixture mode of ductile and brittle. The ductile mode was attributed to the weak bonding strength of fiber/matrix at low temperature. The brittle fracture might be caused by the propagation of micro defect or crack, which existed in the as-prepared composites for the ten-cycle process. 展开更多
关键词 fracture mechanism 3D five-directional SiO2)y/SiO2 composite silicasol-infiltrationsintering method
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Enhanced optical nonlinear absorption of graded Au-TiO_2 composite films 认领 引用 被引量:3
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作者 刘莉 苏雄睿 《Chinese Physics B》 SCIE EI CAS 2008年第6期2170-2174,共5页
This paper reports that single-layer and graded Au-TiO2 granular composite films with Au atom content 15%- 66% were prepared by using reactive co-sputtering technique. The third-order optical nonlinearity of single-la... This paper reports that single-layer and graded Au-TiO2 granular composite films with Au atom content 15%- 66% were prepared by using reactive co-sputtering technique. The third-order optical nonlinearity of single-layer and graded composite films was investigated by using s- and p-polarized Z-scans in femtosecond time scale. The nonlinear absorption coefficient βeff of single-layer Au-TiO2 films is measured to be -2.3×10^3-0.76×10^3 cm/GW with Au atom content 15%-66%. The βeff value of the 10-layer Au-TiO2 graded film is enhanced to be -2.1×10^4cm/GW calculated from p-polarized Z-scans, which is about ten times the maximum βeff of single-layer films. Broadened response in the wavelength region 730-860 nm of the enhanced optical nonlinearity of graded Au-TiO2 composite films was also investigated. 展开更多
关键词 Au-TiO2 granular composites graded composite films Z-scan optical nonlinear absorption
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Structural Characteristics and Photocatalytic Activity of Ambient Pressure Dried SiO2/TiO2 Aerogel Composites by One-step Solvent Exchange/Surface Modification 认领 引用 被引量:3
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作者 徐海珣 朱平华 +2 位作者 WANG Lijiu JIANG Zuqiang 赵善宇 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2016年第1期80-86,共7页
An ambient pressure synthesis of SiO2/TiO2 binary aerogel was prepared through the low-cost precursors of titanium tetrachloride(TiCl4) and sodium silicate(Na2O·nSiO2).After gelation,solvent exchange and surf... An ambient pressure synthesis of SiO2/TiO2 binary aerogel was prepared through the low-cost precursors of titanium tetrachloride(TiCl4) and sodium silicate(Na2O·nSiO2).After gelation,solvent exchange and surface modification were performed simultaneously and the modified gel was finally dried under ambient pressure.Microstructural analyses by transmission electron microscope(TEM) indicate that fabricated SiO2/TiO2 aerogel composite shows similar sponge-like nanostructure as silica aerogel,and the Brunauer-EmmettTeller(BET) analysis shows that the specific surface area of the composite reaches 605 m^2/g,and the average pore size is 9.7 nm.Such binary aerogel exhibits significant photocatalytic performance in this paper for treating model pollutant of methyl orange(MO),and the decolorizing efficiency of MO is detected as 84.9%after 210 mins exposure to UV light irradiation.Degraded gel suspends in the water so as to separate from solution for reuse,and after 4 times recycling,70%degradation efficiency can be easily reached when composite catalyzed system is exposed for 210 mins under UV irradiation. 展开更多
关键词 photocatalytic activity water glass SiO2/TiO2 binary aerogel ambient drying
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