首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 31 毫秒
1.
Visible‐light‐driven Ag/AgBr/TiO2/activated carbon (AC) composite was prepared by solgel method coupled with photoreduction method. For comparison, TiO2, TiO2/AC, and Ag/AgBr/TiO2 were also synthesized. Their characteristics were analyzed by XRD, SEM‐EDS, TG‐DSC and UV–vis techniques. Photocatalytic activity and antibacterial performance under visible‐light irradiation were investigated by ICP‐AES, ATR‐FT‐IR and spectrophotometry methods using methylene blue and Escherichia coli as target systems, respectively. The results showed that Ag/AgBr was successfully deposited on anatase TiO2/AC surface, and exhibited a distinct light absorption in the visible region. Ag/AgBr/TiO2/AC displayed excellent antibacterial performance both in dark and under visible‐light illumination. The growth of E. coli cell was inhibited in the presence of Ag/AgBr/TiO2/AC in dark. Moreover, upon visible‐light illumination, a significant damage of cell membrane was noticed. Ag/AgBr/TiO2/AC was also shown higher photocatalytic efficiency for methylene blue degradation than those of TiO2, TiO2/AC, and Ag/AgBr/TiO2. This is attributed to the synergetic effect between AC and Ag/AgBr/TiO2, of which AC acts as the role of increasing reaction areas, continuous enriching, and transferring the adsorbed MB molecules to the surface of supported photocatalysts, and the Ag/AgBr/TiO2 acts as a highly active photocatalyst for degrading MB molecules under visible‐light irradiation.  相似文献   

2.
Composite nano‐TiO2 with doping Fe3+ and Ag was prepared, and further modified by 3‐methacryloxypropyltrimethoxysilane. They were characterized by Zetasizer Nano ZS Particle and Zeta Potential Analyzer, X‐ray diffraction, UV–Vis spectrophotometer, FT–IR spectra, and transmission electron microscopy. The modified composite nano‐TiO2 was applied to prepare multifunctional fluorocarbon coatings (FCC). Antibacterial activity of multifunctional FCC containing modified composite nano‐TiO2 was investigated. Its photocatalytic antibacterial activity reached 92%. The influence of doping ingredients, amount of composite nano‐TiO2, different light houses, or surface modification was discussed. The surface of FCC cannot be easily smirched by oiliness, dust or water because of hydrophobic fluorosilicone emulsion. It would be an available modern interior building coating for its remarkable photocatalytic antibacterial property as well as self‐cleaning function. Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   

3.
《先进技术聚合物》2018,29(10):2619-2631
In the present work, development of neat and nanocomposite polyethersulfone membranes composed of TiO2 nanoparticles is presented. Membranes are fabricated using nonsolvent phase inversion process with the objective of improving antifouling, hydrophilicity, and mechanical properties for real and synthetic produced water treatment. Membranes are characterized using scanning electron microscopy, Fourier‐transform infrared, contact angle, porosity measurement, compaction factor, nanoparticles stability, and mechanical strength. The performance of prepared membranes was also characterized using flux measurement and oil rejection. Fourier‐transform infrared spectra indicated that noncovalence bond formed between Ti and polyethersulfone chains. The contact angle results confirmed the improved hydrophilicity of nanocomposite membranes upon addition of TiO2 nanoparticles owing to the strong interactions between fillers and water molecules. The increased water flux for nanocomposite membranes in comparison with neat ones can be due to coupling effects of improved surface hydrophilicity, higher porosity, and formation of macrovoids in the membrane structure. The membrane containing 7 wt% of TiO2 nanoparticles was the best nanocomposite membrane because of its high oil rejection, water flux, antifouling properties, and mechanical stability. The pure water flux for this membrane was twice greater than that of neat membrane without any loss in oil rejection. The hydrophilicity and antifouling resistance against oil nominates developed nanocomposite membranes for real and synthetic produced water treatment applications with high performance and extended life span.  相似文献   

4.
A series of Ag‐enhanced TiO2–x/C composites (Ag/TiO2–x/C composites) with metal‐organic frameworks (MOFs) as precursors were prepared, and their photocatalytic activities were evaluated by the UV‐light driven photodegradation behaviors of methyl blue (MB). The as‐obtained samples were characterized by several techniques such as SEM, XRD, N2‐adsorption, XPS, UV/Vis spectrophotometry and UV/Vis diffuse‐reflectance spectra. The best photocatalytic performance was achieved in Ag/TiO2–x/C composite pyrolyzed at 1000 °C (ATC‐P10) due to rapid capture of electrons caused by silver doping, higher density of TiO2–x lattice oxygen vacancies for better trapping of electrons, and high surface area due to reduction and evaporation of metallic Zn. No obvious deactivation was observed after 10 cycles of UV‐light degradation of MB under the same experimental conditions. This report reveals a new approach to prepare stable and highly efficient UV‐light‐driven photocatalysts for organic pollutants in water.  相似文献   

5.
A novel TiO2 nanoparticle self-assembly membrane was prepared based on ultrahigh molecular weight poly(styrene-alt-maleic anhydride)/poly(vinylidene fluoride) (SMA/PVDF) blend membrane. TiO2 nanoparticle solution was beforehand prepared via the controlled hydrolysis of titanium tetraisopropoxide. The diameter (10 nm or less) and anatase crystal structure were analyzed using transmission electron microscopy (TEM) and X-ray diffraction (XRD). The SMA/PVDF blend membranes prepared by the phase inversion method were immersed into the TiO2 nanoparticle solution for a week to produce TiO2 self-assembly membranes. The chemical compositions in membrane surface were analyzed by X-ray photoelectron spectroscopy (XPS). The membrane morphologies were measured by scanning electron microscopy (SEM). Finally, the membrane hydrophilicity, protein anti-fouling property and the molecular weight cutoff (MWCO) were characterized by water contact angle measurement, static protein absorption and filtration experiments, respectively. It is demonstrated that, in comparison to PVDF/SMA blend membrane, the permeability and anti-fouling ability of TiO2 self-assembly membranes were significantly improved.  相似文献   

6.
ZnTiO3–TiO2/organic pillared montmorillonite (pMt) composite catalyst was successfully prepared in this paper by immobilizing ZnTiO3–TiO2 onto pMt. The composition and texture of the prepared composite catalyst were characterized by X-ray diffraction, Raman spectroscopy, Fourier transform infrared spectroscopy, transmission electron microscopy, energy dispersive spectrometry, ultraviolet–visible light (UV–Vis) diffuse reflectance spectroscopy and X-ray photoelectron spectroscopy. The photocatalytic activity was tested via photocatalytic degradation of methyl blue (MB) under both visible irradiation and UV light. The results indicated that the ZnTiO3–TiO2/pMt composite catalyst had an apparent absorption at the area of visible irradiation, and exhibited a higher efficiency of photocatalytic degredation of MB under visible irradiation. This was due to the heterostructure of ZnTiO3–TiO2, and the mesoporous structure and specific surface area of the ZnTiO3–TiO2/pMt composite. In addition, the results of the radical scavenging experiments showed that the holes and superoxide radicals are responsible for the degradation of MB under visible irradiation.  相似文献   

7.
《先进技术聚合物》2018,29(4):1303-1312
New thin film composite (TFC) membrane was prepared via coating of Pebax on PSf‐PES blend membrane as support, and its application in wastewater treatment was investigated. To modify this membrane, hydrophilic TiO2 nanoparticles were coated on its surface at different loadings via dip coating technique. The as‐prepared membrane was characterized using Fourier transform infrared spectroscopy, scanning electron microscopy (SEM), field emission SEM, and contact angle analysis. The Fourier transform infrared spectroscopy analysis and surface SEM images indicated that TiO2 was successfully coated on the membrane surface. In addition, the results stated that the hydrophilicity and roughness of membrane surface increased by addition of TiO2 nanoparticles. Performance of TFC and modified TFC membranes was evaluated through humic acid removal from aqueous solution. Maximum permeate flux and humic acid rejection were obtained at 0.03 and 0.01 wt% TiO2 loadings, respectively. Rejection was enhanced from 96.38% to 98.92% by the increase of feed concentration from 10 to 30 ppm. Additionally, membrane antifouling parameters at different pressures and feed concentration were determined. The results indicated that surface modification of membranes could be an effective method for improvement of membrane antifouling property.  相似文献   

8.
PVDF/(PEI‐C/PAA)n functional membranes were prepared by layer‐by‐layer (LbL) assembly, and their heavy metal ions adsorption capability was investigated. The changes in the chemical compositions of membrane surfaces were determined by X‐ray photoelectron spectroscopy (XPS). XPS results show that the surface of the PVDF membrane can be alternatively functionalized by PEI‐C and PAA. The membrane surface hydrophilicity was evaluated through water contact angle measurement. Contact angle results show that the surface hydrophilicity of the membrane surface depends on the outermost deposited layer. Morphological changes of membrane surfaces were observed by scanning electron microscopy (SEM). The water fluxes for these membranes were elevated after modification. The performances of the PVDF/(PEI‐C/PAA)n membranes on the adsorption of copper ions (Cu2+) from aqueous solutions were investigated by inductively coupled plasma (ICP). The results indicate that the PVDF/(PEI‐C/PAA)n functional membranes show high copper ions adsorption ability. Copyright © 2010 John Wiley & Sons, Ltd.  相似文献   

9.
Titanium dioxide (TiO2) nanoparticles were assembled on the surface of nanofiltration blend membrane. For settling TiO2 on the membrane surface, two membrane categories were used: (i) unmodified polyethersulfone (PES)/polyimide (PI) blend membrane, and (ii) –OH functionalized PES/PI blend membrane with different concentrations of diethanolamine (DEA). These membranes were radiated by UV light after TiO2 depositing with different concentrations. 15 min immersion in colloidal suspension and 15 min UV irradiation with 160 W lamps were used for modification. The modification resulted in the formation of a photo-catalytic property with enhanced membrane hydrophilicity. The self-assembly of TiO2 nanoparticles was established through coordinance bonds with –OH functional groups on the membrane surface. A comparison between the UV irradiated TiO2 deposited blend membrane and deposited-functionalized blend membranes showed that –OH groups originate excellent adhesion of TiO2 nanoparticles on the membrane surface, increase reversible deposition, and diminish irreversible fouling. The membranes were characterized using SEM, FTIR, EDX, contact angle, cross flow filtration, and antifouling measurements. SEM images show that the presence of –OH groups on the DEA-modified membrane surface is the main parameter for extra uniformly settlement of TiO2 nanoparticles on the membrane surface. This procedure is a superior technique for modification of PES/PI nanofiltration membranes to enhance water flux and minimization membrane fouling.  相似文献   

10.
The influence of inorganic filler TiO2 nanoparticles on the morphology and properties of polysulfone (PS) ultrafiltration membranes was investigated. PS/TiO2 composite membranes were prepared by a phase‐inversion method. TiO2 nanoparticles modified by sodium dodecyl sulfate were uniformly dispersed in an 18 wt % PS casting solution. The addition of TiO2 resulted in an increase in the pore density and porosity of the membrane skin layer. The pore size distribution changed from the log‐normal distribution to the bimodal distribution because of the presence of TiO2 nanoparticles, and some large pores were observed when the concentration of the filler was over 3 wt %. The skin layer was gradually thickened; meanwhile, the morphology sublayer changed from macrovoids to spongelike pores, in comparison with PS membranes without the filler. The addition of TiO2 also induced increases in the hydrophilicity, mechanical strength, and thermal stability. The ultrafiltration experiments showed when the concentration of TiO2 was less than 2 wt %, the permeability and rejection of the membrane was enhanced and then decreased drastically with a higher filler concentration (>3%). © 2006 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 44: 879–887, 2006  相似文献   

11.
Poly(vinylidene fluoride) (PVDF) membranes were hydrophilic modified with hydroxyl group terminated hyperbranched poly(amine‐ester) (HPAE). Fourier transform infrared spectroscopy (FT‐IR) was used to study the chemical change of PVDF membranes. X‐ray photoelectron spectroscopy (XPS) indicated that some HPAE molecules were retained in PVDF membrane through polymer chain coiling. The presence of HPAE would improve the hydrophilicity of PVDF membrane. Scanning electron microscopy (SEM) was employed to characterize the morphology of different membranes. The thermodynamic stability for PVDF/DMAc/HPAE/Water system was characterized by the determination of the gelation values. Precipitation kinetics for PVDF/DMAc/HPAE/Water system was studied by precipitation time measurement. The water contact angle indicated that the hydrophilicity and the biocompatibility corresponding to protein adsorption of PVDF membrane were improved significantly after blending with hydrophilic HPAE molecules. Copyright © 2011 John Wiley & Sons, Ltd.  相似文献   

12.
以乙醇为溶剂, 钛酸四丁酯为前驱体, 用溶剂热法制备了Ag表面修饰的负载型纳米二氧化钛光催化剂. 利用X射线衍射(XRD)、N2吸附-脱附(BET)、透射电子显微镜(TEM)、X射线光电子能谱(XPS)、紫外-可见(UV-Vis)光谱等技术对其进行了系统的表征, 以亚甲基蓝(MB)溶液的脱色降解为模型反应, 考察了不同Ag含量样品的光催化性能. 结果表明: 用溶剂热法制备的样品中TiO2皆为锐钛矿相, 金属Ag颗粒沉积在TiO2表面, 粒径为2 nm左右, 比表面积较溶胶凝胶法制备的样品大大增加, 最高可达151.44 m2·g-1; UV-Vis光谱和光催化实验表明: Ag修饰使TiO2对光的吸收能力大大增强, 吸收带边红移至可见光区, 亚甲基蓝在该复合材料上的光催化降解反应遵循一级反应动力学模型; 溶剂热法制备样品的光催化性能明显好于溶胶凝胶法制备的样品, 在紫外光和可见光下, Ag摩尔分数为5%的样品表现出最佳的光催化活性.  相似文献   

13.
以乙醇为溶剂, 钛酸四丁酯为前驱体, 用溶剂热法制备了Ag表面修饰的负载型纳米二氧化钛光催化剂. 利用X射线衍射(XRD)、N2吸附-脱附(BET)、透射电子显微镜(TEM)、X射线光电子能谱(XPS)、紫外-可见(UV-Vis)光谱等技术对其进行了系统的表征, 以亚甲基蓝(MB)溶液的脱色降解为模型反应, 考察了不同Ag含量样品的光催化性能. 结果表明: 用溶剂热法制备的样品中TiO2皆为锐钛矿相, 金属Ag颗粒沉积在TiO2表面, 粒径为2 nm左右, 比表面积较溶胶凝胶法制备的样品大大增加, 最高可达151.44 m2·g-1; UV-Vis光谱和光催化实验表明: Ag修饰使TiO2对光的吸收能力大大增强, 吸收带边红移至可见光区, 亚甲基蓝在该复合材料上的光催化降解反应遵循一级反应动力学模型; 溶剂热法制备样品的光催化性能明显好于溶胶凝胶法制备的样品, 在紫外光和可见光下, Ag摩尔分数为5%的样品表现出最佳的光催化活性.  相似文献   

14.
以乙醇为溶剂, 钛酸四丁酯为前驱体, 用溶剂热法制备了Ag表面修饰的负载型纳米二氧化钛光催化剂. 利用X射线衍射(XRD)、N2吸附-脱附(BET)、透射电子显微镜(TEM)、X射线光电子能谱(XPS)、紫外-可见(UV-Vis)光谱等技术对其进行了系统的表征, 以亚甲基蓝(MB)溶液的脱色降解为模型反应, 考察了不同Ag含量样品的光催化性能. 结果表明: 用溶剂热法制备的样品中TiO2皆为锐钛矿相, 金属Ag颗粒沉积在TiO2表面, 粒径为2 nm左右, 比表面积较溶胶凝胶法制备的样品大大增加, 最高可达151.44 m2·g-1; UV-Vis光谱和光催化实验表明: Ag修饰使TiO2对光的吸收能力大大增强, 吸收带边红移至可见光区, 亚甲基蓝在该复合材料上的光催化降解反应遵循一级反应动力学模型; 溶剂热法制备样品的光催化性能明显好于溶胶凝胶法制备的样品, 在紫外光和可见光下, Ag摩尔分数为5%的样品表现出最佳的光催化活性.  相似文献   

15.
以乙醇为溶剂, 钛酸四丁酯为前驱体, 用溶剂热法制备了Ag表面修饰的负载型纳米二氧化钛光催化剂. 利用X射线衍射(XRD)、N2吸附-脱附(BET)、透射电子显微镜(TEM)、X射线光电子能谱(XPS)、紫外-可见(UV-Vis)光谱等技术对其进行了系统的表征, 以亚甲基蓝(MB)溶液的脱色降解为模型反应, 考察了不同Ag含量样品的光催化性能. 结果表明: 用溶剂热法制备的样品中TiO2皆为锐钛矿相, 金属Ag颗粒沉积在TiO2表面, 粒径为2 nm左右, 比表面积较溶胶凝胶法制备的样品大大增加, 最高可达151.44 m2·g-1; UV-Vis光谱和光催化实验表明: Ag修饰使TiO2对光的吸收能力大大增强, 吸收带边红移至可见光区, 亚甲基蓝在该复合材料上的光催化降解反应遵循一级反应动力学模型; 溶剂热法制备样品的光催化性能明显好于溶胶凝胶法制备的样品, 在紫外光和可见光下, Ag摩尔分数为5%的样品表现出最佳的光催化活性.  相似文献   

16.
以乙醇为溶剂, 钛酸四丁酯为前驱体, 用溶剂热法制备了Ag表面修饰的负载型纳米二氧化钛光催化剂. 利用X射线衍射(XRD)、N2吸附-脱附(BET)、透射电子显微镜(TEM)、X射线光电子能谱(XPS)、紫外-可见(UV-Vis)光谱等技术对其进行了系统的表征, 以亚甲基蓝(MB)溶液的脱色降解为模型反应, 考察了不同Ag含量样品的光催化性能. 结果表明: 用溶剂热法制备的样品中TiO2皆为锐钛矿相, 金属Ag颗粒沉积在TiO2表面, 粒径为2 nm左右, 比表面积较溶胶凝胶法制备的样品大大增加, 最高可达151.44 m2·g-1; UV-Vis光谱和光催化实验表明: Ag修饰使TiO2对光的吸收能力大大增强, 吸收带边红移至可见光区, 亚甲基蓝在该复合材料上的光催化降解反应遵循一级反应动力学模型; 溶剂热法制备样品的光催化性能明显好于溶胶凝胶法制备的样品, 在紫外光和可见光下, Ag摩尔分数为5%的样品表现出最佳的光催化活性.  相似文献   

17.
以乙醇为溶剂, 钛酸四丁酯为前驱体, 用溶剂热法制备了Ag表面修饰的负载型纳米二氧化钛光催化剂. 利用X射线衍射(XRD)、N2吸附-脱附(BET)、透射电子显微镜(TEM)、X射线光电子能谱(XPS)、紫外-可见(UV-Vis)光谱等技术对其进行了系统的表征, 以亚甲基蓝(MB)溶液的脱色降解为模型反应, 考察了不同Ag含量样品的光催化性能. 结果表明: 用溶剂热法制备的样品中TiO2皆为锐钛矿相, 金属Ag颗粒沉积在TiO2表面, 粒径为2 nm左右, 比表面积较溶胶凝胶法制备的样品大大增加, 最高可达151.44 m2·g-1; UV-Vis光谱和光催化实验表明: Ag修饰使TiO2对光的吸收能力大大增强, 吸收带边红移至可见光区, 亚甲基蓝在该复合材料上的光催化降解反应遵循一级反应动力学模型; 溶剂热法制备样品的光催化性能明显好于溶胶凝胶法制备的样品, 在紫外光和可见光下, Ag摩尔分数为5%的样品表现出最佳的光催化活性.  相似文献   

18.
以乙醇为溶剂, 钛酸四丁酯为前驱体, 用溶剂热法制备了Ag表面修饰的负载型纳米二氧化钛光催化剂. 利用X射线衍射(XRD)、N2吸附-脱附(BET)、透射电子显微镜(TEM)、X射线光电子能谱(XPS)、紫外-可见(UV-Vis)光谱等技术对其进行了系统的表征, 以亚甲基蓝(MB)溶液的脱色降解为模型反应, 考察了不同Ag含量样品的光催化性能. 结果表明: 用溶剂热法制备的样品中TiO2皆为锐钛矿相, 金属Ag颗粒沉积在TiO2表面, 粒径为2 nm左右, 比表面积较溶胶凝胶法制备的样品大大增加, 最高可达151.44 m2·g-1; UV-Vis光谱和光催化实验表明: Ag修饰使TiO2对光的吸收能力大大增强, 吸收带边红移至可见光区, 亚甲基蓝在该复合材料上的光催化降解反应遵循一级反应动力学模型; 溶剂热法制备样品的光催化性能明显好于溶胶凝胶法制备的样品, 在紫外光和可见光下, Ag摩尔分数为5%的样品表现出最佳的光催化活性.  相似文献   

19.
以乙醇为溶剂, 钛酸四丁酯为前驱体, 用溶剂热法制备了Ag表面修饰的负载型纳米二氧化钛光催化剂. 利用X射线衍射(XRD)、N2吸附-脱附(BET)、透射电子显微镜(TEM)、X射线光电子能谱(XPS)、紫外-可见(UV-Vis)光谱等技术对其进行了系统的表征, 以亚甲基蓝(MB)溶液的脱色降解为模型反应, 考察了不同Ag含量样品的光催化性能. 结果表明: 用溶剂热法制备的样品中TiO2皆为锐钛矿相, 金属Ag颗粒沉积在TiO2表面, 粒径为2 nm左右, 比表面积较溶胶凝胶法制备的样品大大增加, 最高可达151.44 m2·g-1; UV-Vis光谱和光催化实验表明: Ag修饰使TiO2对光的吸收能力大大增强, 吸收带边红移至可见光区, 亚甲基蓝在该复合材料上的光催化降解反应遵循一级反应动力学模型; 溶剂热法制备样品的光催化性能明显好于溶胶凝胶法制备的样品, 在紫外光和可见光下, Ag摩尔分数为5%的样品表现出最佳的光催化活性.  相似文献   

20.
以乙醇为溶剂, 钛酸四丁酯为前驱体, 用溶剂热法制备了Ag表面修饰的负载型纳米二氧化钛光催化剂. 利用X射线衍射(XRD)、N2吸附-脱附(BET)、透射电子显微镜(TEM)、X射线光电子能谱(XPS)、紫外-可见(UV-Vis)光谱等技术对其进行了系统的表征, 以亚甲基蓝(MB)溶液的脱色降解为模型反应, 考察了不同Ag含量样品的光催化性能. 结果表明: 用溶剂热法制备的样品中TiO2皆为锐钛矿相, 金属Ag颗粒沉积在TiO2表面, 粒径为2 nm左右, 比表面积较溶胶凝胶法制备的样品大大增加, 最高可达151.44 m2·g-1; UV-Vis光谱和光催化实验表明: Ag修饰使TiO2对光的吸收能力大大增强, 吸收带边红移至可见光区, 亚甲基蓝在该复合材料上的光催化降解反应遵循一级反应动力学模型; 溶剂热法制备样品的光催化性能明显好于溶胶凝胶法制备的样品, 在紫外光和可见光下, Ag摩尔分数为5%的样品表现出最佳的光催化活性.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号