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1.
反胶束法制备纳米粒子是 2 0世纪 80年代兴起的研究领域[1] .反胶束是指表面活性剂在非极性溶剂中定向排列而自发形成的聚集体 [2 ] ,反胶束的“水池”是一种特殊的纳米空间 ,以此作为微反应器 ,通过控制含水量 W0 ( W0 =[H2 O]/[Surft.],即水与表面活性剂的摩尔比 )和选择不同的表面活性剂种类及浓度可以获得单分散的粒径小于 1 0 nm的微粒 [3~ 5] .Ti O2 作为一种典型的光催化剂 ,由于其化学性质稳定、氧化还原性强 ,且具有抗光阴极腐蚀性、难溶、无毒、成本低等特点 ,在有机污染物的去除 ,废水处理等方面具有广阔的应用前景[6 ] .而…  相似文献   

2.
反胶束体系制备负载型TiO2纳米光催化剂   总被引:7,自引:0,他引:7  
在AOT/异辛烷反胶束体系中制备了粒径为2~5nm的单分散球形TiO2纳米粒子,用TEM,DSC和XRD等手段对其进行了分析;用浸渍法以小孔分子筛HZSM-5为载体制备了负载型TiO2纳米粒子,用FTIR,Langmuir及BET等手段进行了表征;用以上2种TiO2粒子作光催化剂进行了简单模拟废水处理研究,用UV-Vis光谱分析其催化效果表明,负载型TiO2纳米粒子比纯TiO2纳米粒子的光催化活性更高.  相似文献   

3.
TiO_2纳米粒子的表面修饰研究   总被引:1,自引:0,他引:1  
利用表面修饰法合成了油酸 (OA)修饰的TiO2 纳米粒子 ,采用红外光谱 (IR)、透射电子显微镜 (TEM)和X射线光电子能谱 (XPS)对表面修饰的TiO2 纳米粒子进行了结构表征 ,并研究了油酸浓度对TiO2 表面覆盖量及在油中分散性能的影响 .研究结果表明通过油酸表面修饰 ,成功合成了具有油分散性能的纳米TiO2 ,并且获得了油酸修饰量与TiO2 的最佳配比 .  相似文献   

4.
分别以阴离子表面活性剂二(2-乙基己基)丁二酸酯磺酸钠(AOT)和新型表面活性剂二(2-乙基己基)羟基丁二酸酯磺酸钠(AHOT)与异辛烷/水构建的反胶束体系为微反应器,合成了CoFe2O4纳米粒子;利用TGA,XRD,TEM等手段对产物进行了表征;讨论了两种表面活性剂构建的反胶束体系对产物合成过程及纳米粒子形貌和尺寸的影响.  相似文献   

5.
氢氧化铝对纳米TiO2的表面包覆   总被引:4,自引:0,他引:4  
氢氧化铝对纳米TiO2的表面包覆;纳米TiO2;氢氧化铝;包覆;光稳定性  相似文献   

6.
宋根萍  郭荣 《应用化学》2000,17(2):195-197
十二烷基苯磺酸钠胶束体系中聚苯乙烯/α-Fe2O3复合纳米粒子的制备  相似文献   

7.
聚苯胺纳米粒子的反胶束法合成及自组装   总被引:3,自引:0,他引:3  
邢双喜  褚莹  隋晓萌 《应用化学》2004,21(12):1315-0
聚苯胺纳米粒子的反胶束法合成及自组装;聚苯胺;纳米粒子;反胶束;自组装  相似文献   

8.
表面修饰的二氧化锡纳米粒子的制备及微结构表征   总被引:11,自引:0,他引:11  
采用胶体化学制得表面包覆有DBS的二氧化锡纳米粒子,并运用一系列手段对其微结构进行了表征。  相似文献   

9.
TiO2纳米粒子膜催化剂光催化降解水中污染物,与粉末相比具有可重复使用、易回收等优点,近年来,在光化学领域受到人们的高度重视[1~3].膜催化剂的表面性质与其光催化活性直接相关,研究这些性质能够为研制、开发高效催化剂提供理论依据.本文采用TiCl4水解法,制备了酸性、碱性条件下TiO2纳米粒子膜.利用原子力显微镜(AFM)、X-射线衍射谱(XRD)、红外光谱(IR)和场诱导表面光电压谱(EFISPS)测定其表面微结构.考察了它们对苯酚降解的光催化活性,讨论了膜催化剂的表面性质对光催化活性的影响.  相似文献   

10.
TiO2纳米粒子膜表面性质的研究   总被引:14,自引:0,他引:14  
TiO_2纳米粒子膜在光催化降解大气和水中的污染物[1]、光电转换[2]、光致变色[3]等方面有广阔的应用前景,近年来受到了科学界的高度重视.研究表明,膜的表面性质对如上应用有着重要影响.本文采用等离子体化学气相沉积法(PECVD法)[4]制备了TiO2的纳米粒子膜,分别采用TiCl4等离子体或O2等离子体处理膜表面,获得两种不同表面性质的TiO2纳米粒子膜;并利用表面光电压谱(SPS)和电场诱导表面光电压谱(EFISPS)技术对膜的表面性质进行具体分析,探讨了其在光催化领域的可能应用.1实验部…  相似文献   

11.
染料敏化太阳电池(DSC)作为新型太阳电池自问世以来受到了广泛关注, 其系统内部的接触界面尤其是TiO2/染料/电解质界面一直是该领域的研究热点. 光敏染料的吸附以及电子的注入、传输和复合都发生在该界面, 其界面性质对DSC性能具有很大影响. 对染料敏化太阳电池中TiO2/染料/电解质界面进行修饰可以有效抑制染料聚集和电子复合, 提高电子的注入效率与传输速率; 同时, 对TiO2导带边的位置及染料吸附等也产生一定的影响, 最终提高电池的光电转换效率和稳定性. 本文主要从不同的修饰途径详细评述了TiO2/染料/电解质界面修饰方法及机理研究进展,包括TiO2光阳极的修饰改性、染料溶液中共吸附剂的引入和多种染料共敏化处理以及电解质中不同功能添加剂的应用. 指出了这些修饰方法目前存在的主要问题, 并对未来的发展方向进行了展望.  相似文献   

12.
纳米TiO2有机表面改性的研究   总被引:26,自引:0,他引:26  
利用硅烷偶联剂(KH-550)对表面包覆氧化硅的金红石相纳米TiO2进行了有机表面改性。采用红外光谱(IR)、X射线光电子能谱(XPS)、热分析(TG-DTA)、BET、透射电镜(TEM)、润湿性和分散性实验等对表面改性前后的纳米TiO2进行了表征。红外光谱和X射线光电子能谱表明,KH-550以化学键合的方式结合在纳米TiO2的表面,并形成了有机包覆层。经测量,纳米TiO2表面的KH-550的质量分数约为2.0%。讨论了产生KH-550理论包覆量与实际包覆量差异的原因。TEM、TG和BET得出的结果显示,在纳米TiO2有机表面改性过程中存在明显的团聚现象,改进分散纳米TiO2的方法是提高有机改性效果的关键。润湿性实验和分散性实验表明,经KH-550表面改性的纳米TiO2同时具有亲水性和亲油性。  相似文献   

13.
MENG Zeda  OH Wonchun 《催化学报》2012,(9):1495-1501
CoS2,CoS 2-C60 /TiO2,CoS2-CNT/TiO2,and CoS2-Graphene/TiO2 were prepared.The TiO2 products had the anatase phase structure and interesting surface compositions.X-ray diffraction patterns of the CoS2-carbon/TiO2 composites showed a single and clear anatase phase and the CoS2 structure.Scanning electron microscopy characterization of the texture on the CoS 2-carbon/TiO2 composites showed a homogenous composition.Energy-dispersive X-ray spectra for elemental identification showed the presence of C and Ti with strong Co and S peaks from the CoS2-carbon/TiO2 composites.The composites obtained were also characterized by transmission electron microscopy and UV-Vis spectroscopy.CoS2-carbon/TiO2 composites showed excellent photocatalytic activity for the degradation of methylene blue under visible light irradiation.This was attributed to both photocatalysis on the TiO2 support and charge transfer by the carbon nanomaterial,and the introduction of CoS2 to enhance transfer of photogenerated electrons.  相似文献   

14.
The complexes Ti(OCH2CH2O)2 and Zr(OCH2CH2O)2 were directly synthesized by using HOCH2CH2OH dissolution in 50 mL flask. The nano-ZrO2 / TiO2 powders were prepared by a direct sol-gel synthesis using the above solution and followed by drying at 400 ℃ for 2 h. The complexes were characterized by FTIR and 1H NMR. XRD and TEM were used to investigate the structure of nano-ZrO2 / TiO2. The results show that the complexes containing -OCH2CH2O- group could prevent the precursor from agglomeration and sintering during the hydrolysis and calcination process. The ZrO2 / TiO2 powders of 20~35 nm was thus obtained in a high purity. The highly active nano-ZrO2 / TiO2 modified electrode was prepared by using daubing and calcination. The electro-catalytic activities of this electrode in (COOH)2 were investigated. The discharge current of nano-ZrO2 / TiO2 electrode increased obviously. In preparative electrolysis under optimal conditions, the average yield and current efficiency for HOOC-CHO were 84.7% and 91.6 %, respectively.  相似文献   

15.
Self-made TiO2 nanoparticles were used as photoelectrode material of dye sensitized solar cell. The TiO2 thin film coats through spreading nanoparticles evenly onto the ITO glass via self-made spin-heat platform, and then TiO2 thin film is soaked in the dye N-719 more than 12 h to prepare the photoelectrode device. The TiO2 nanoparticles produced by electric-discharge-nanofluid-process have premium anatase crystal property, and its diameter can be controlled within a range of 20-50 nm. The surface energy zeta potential of nanofluid is from -22 mV to -28.8 mV, it is a stable particle suspension in the deionized water. A trace of surfactant Triton X-100 put upon the surface of ITO glass can produce a uniform and dense TiO2 thin film and heating up the spin platform to 200 oC is able to eliminate mixed surfac-tant. Self-made TiO2 film presents excellent dye absorption performance and even doesn't need heat treatment procedure to enhance essential property. Results of energy analysis show the thicker film structure will increase the short-circuit current density that causes higher conversion efficiency. But, as the film structure is large and thick, both the open-circuit voltage and fill factor will decline gradually to lead bad efficiency of dye-sensitized solar cell.  相似文献   

16.
以水溶性C60和TiO2粒子为前驱体,采用水热法制备了载有C60的锐钛矿型TiO2纳米粒子。应用X射线衍射、透射电子显微镜、红外光谱、紫外-可见漫反射光谱、荧光光谱对产物进行了表征。以对-硝基苯酚为模型污染物研究了产物的光催化活性,结果表明适量负载C60可以提高TiO2纳米粒子的光催化活性,C60起着传输电子、促进TiO2光生载流子分离的作用,且经7次循环使用后对-硝基苯酚的降解效率仍能达到74%。讨论了载有C60的TiO2纳米粒子光催化降解对-硝基苯酚的机理。  相似文献   

17.
同轴静电纺丝法在纳米中空TiO2纤维中填充Ag的应用   总被引:1,自引:0,他引:1  
以聚乙烯吡咯烷酮(PVP)溶胶/钛酸四正丁酯和PVP溶胶/银颗粒为前驱体, 以共轴静电纺丝法制备了银填充的TiO2中空纳米纤维. 将双组分纤维在200 ℃下热处理去除乙醇与表面吸附水后, 继而在空气气氛中焙烧至600 ℃, 可以得到在内表面上沉积银颗粒的TiO2纳米管, 银颗粒的直径为5-40 nm, TiO2纳米管的外径150-300 nm, 管臂厚10-20 nm. 用红外吸收光谱(IR)、X射线衍射(XRD)、扫描电子显微镜(SEM)、透射电子显微镜(TEM)等测试手段对超细纤维进行了表征. 中空纤维的直径和管壁可以通过改变电纺参数来调节. 与Ag-TiO2纳米纤维、TiO2纳米中空纤维、TiO2纳米纤维及TiO2纳米粉体相比较, Ag颗粒填充的TiO2纳米中空纤维在光分解亚甲基蓝上表现出了更好的光催化性能.  相似文献   

18.
钛酸酯偶联剂对包硅铝钛白粉表面的有机改性   总被引:25,自引:0,他引:25  
The surface organic modification of TiO2 particles with titanate coupling reagent,which was pre-coated with double layers of SiO2 and Al2O3,was studied.Experiments showed that the modified particles exhibited hydrophobic characteristics.The modification state of the particle surface was characterized by IR spectroscopic measurement,pyrolytic gas chromatography,thermogravimetric analysis and X-ray photoelectron spectra.The titanate coupling reagent binding with the hydroxyl on the particle surface was analyzed.The surface characteristics of pre-modification and post-modification particles were compared.  相似文献   

19.
Guoqing Chang 《Acta Physico》2008,24(10):1790-1797
This study investigated the coaxial electrospinning process of silver filling in TiO2 ultrafine hollow fibers using polyvinyl pyrrolidone (PVP) sol/titanium n-butyloxide (Ti(OC4H9)4) and PVP sol/silver nanoparticles as pore-directing agents. The bicomponent fibers were heat treated at 200 °C and calcined at 600 °C. Silver particles having diameters of 5 to 40 nm were deposited on the inner surface of the long hollow TiO2 nanofibers (outer diameter of 150.300 nm) with mesoporous walls (thickness of 10.20 nm). The morphological structure of the filled ultrafine hollow fibers has been studied by means of infrared (IR) spectrum, X-ray diffraction (XRD), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). The diameters and wall thicknesses of the hollow fibers could be tuned by adjusting the electrospinning parameters. Compared with other nanostructured TiO2 materials, such as mesoporous Ag-TiO2 blending fibers, TiO2 hollow nanofibers, TiO2 nanofibers, and TiO2 powders, the silver filled TiO2 hollow fibers exhibited a higher photocatalytic activity toward the degradation of methylene blue.  相似文献   

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