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1.
ZrO_2/TiO_2复合光催化膜的微弧氧化法制备及表征   总被引:1,自引:0,他引:1  
采用微弧氧化方法和原位生成的Zr(OH)_4胶体颗粒,在纯钛基体上制备ZrO_2/TiO_2复合光催化膜。采用SEM、EDX、XRD、UV-VisDRS等分析手段,对膜层进行分析表征。结果表明:复合膜显示出层状和多孔的结构,由锐钛矿、金红石和ZrO_2组成;相对于纯TiO_2膜,复合膜层的光吸收截止边缘产生红移;ZnO_2/TiO_2复合膜层和纯TiO_2膜层在紫外光照射下,对罗丹明B的光催化速率常数分别为0.0442和0.0186h~(-1)。  相似文献   

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The novel composite films containing clustered TiO2 particles and fine tourmaline particles on the surface of copper webs were prepared by the sol-gel method. The microstructures of the composite films were investigated by scanning electron microscopy (SEM), and the photocatalytic activity of the films was evaluated by photocatalytic degradation of methyl orange, respectively. The results indicate that tourmaline particles can obviously influence the microstructures of TiO2 films and enhance the photocatalytic activity due to their spontaneous permanent polarity and high radiotechnology of far infrared. During preparing the composite films, the clustered TiO2 particles with lots ofnano-sized ladder layers can grow on the surface of fine tourmaline particles, the thickness of ladder layer is 10 nm, and the average diameter ofnano-sized TiO2 particles is 15 nm.  相似文献   

4.
Ce-TiO2/硅藻土的制备、表征及其光催化活性   总被引:5,自引:3,他引:5  
以硅藻土(KL)为载体,用溶胶-凝胶法将铈掺杂二氧化钛包覆在硅藻土上(Ce-TiO2/KL)。采用XRD、DRS、SEM对其进行表征,以250 W高压汞灯作光源,甲醛作为反应底物表征其光催化活性。结果表明:Ce-TiO2包覆在硅藻土颗粒上,并能在较高的煅烧温度(500℃)范围内保持锐钛矿晶体结构;随着铈掺杂含量的提高,J2Ce-TiO2/KL对可见光的吸收明显增强,有利于充分利用太阳光。由此可见,TiO2固定在硅藻土上时,铈掺杂不仅提高了其活性,还导致其激发波长红移,还有利于回收利用。  相似文献   

5.
采用正交设计方法,试验研究了4种因素对溶胶-凝胶法制备纳米TiO2光催化活性的影响,确定了各因素所对应的最佳水平,得到了溶胶-凝胶法制备高光催化活性纳米TiO2的最佳工艺条件;且对最佳工艺条件制备的TiO2和商业粉P-25进行了XRD和UV-Vis吸收光谱分析。结果表明,自制的TiO2由纯锐钛矿组成,其平均晶粒尺寸为18.2nm,比混晶型的P-25TiO2晶粒尺寸(24.7nm)要小。自制TiO2粉在330~370nm的紫外光区的吸收增强,在可见光区的吸收也较P-25有所增强。两者都有利于光催化活性的提高,使得光催化降解甲基橙的活性与P-25相当。  相似文献   

6.
1 INTRODUCTIONHeterogeneousphotocatalysishasbeenwidelyin vestigatedasanalternativemethodfordegradationoforganicpollutantsinrecent 2 0 years .TiO2 isthemostinvestigatedphotocatalystuptodatebecauseitisoftenusedinthetreatmentofpollutantchemicals ,basedonitsremarkableactivity ,chemicalstability ,andalsoonitsnon toxicproperties.Phenolor phenoliccompoundsexistwidelyindailylifeandinindustrialwastewateroriginatingfromcokeovens ,petroleummanufactureorpaintstrippingoperations ,andhavebecomecommonp…  相似文献   

7.
采用溶胶-凝胶法,以Ti(OC4H9)4和氨水等为原料制备纯二氧化钛、N掺杂以及N,Zn^2+共掺杂的二氧化钛光催化薄膜。用X射线衍射和X光电子能谱等对薄膜进行了表征,紫外光和可见光下催化剂降解甲基橙溶液的实验结果表明,掺杂TiO2薄膜比无掺杂TiO2薄膜的光催化效率明显提高,并且可见光下对甲基橙溶液有一定的光催化活性,但Zn^2+的存在对掺杂薄膜的光催化效率没有显著改善。分析原因可能是N掺杂在价带和导带之间形成了缺陷能级,减小了TiO2的禁带能隙,从而使TiO2的吸收带发生红移,实现可见光响应。  相似文献   

8.
光催化二氧化钛薄膜的制备工艺研究进展   总被引:3,自引:0,他引:3  
评述了制备二氧化钛薄膜的液相法、气相法和电化学法3大类方法的优缺点,以及3大类方法所包含的溶胶-凝胶、微乳液、磁控溅射、物理气相沉积、化学气相沉积、阳极氧化和微弧氧化等方法制备二氧化钛薄膜的工艺步骤、特点及研究进展。文章最后指出,液相法由于自身存在的优点,仍将是今后二氧化钛薄膜制备和研究的重点;而光催化性能更好的掺杂二氧化钛,其研究重点是探讨掺杂方式、制备方法和优化配比等。  相似文献   

9.
表面光催化还原铁对TiO2/SiO2光催化活性的影响   总被引:5,自引:2,他引:5  
用表面光催化还原铁法对TiO2 /SiO2 复合氧化物进行改性 ,并在改性后用XRD ,TEM进行化学状态、晶体组成与颗粒大小分析。通过对亚甲基蓝的降解揭示表面光还原对催化剂活性的影响。结果表明 :经过表面光催化还原铁法改性的催化剂活性要高于未改性的 ,随着表面还原Fe量的增加 ,催化活性增加。但n(Fe)∶n(Ti) >1.0 %后 ,催化性能急剧下降 ,最佳值为 1.0 %。讨论了Fe杂质对光生载流子分离效率的影响及其影响光催化剂活性的机理。Fe3 + 和Fe2 + 共同存在 ,Fe3 + 是光生电子的捕获阱 ,Fe2 + 是光生空穴的捕获阱 ,在二者的协同作用下 ,载流子得到有效分离 ,催化活性得到提高。  相似文献   

10.
1INTRODUCTIONHeterogeneous photocatalysis attracts muchattention as a friendly environment technique valu-able for water and air purification.However,thereare some problems in application,and one of thekey problems is the low photon-quantum efficien-cy.From1990s,the modification of Ti O2by metalions has become a hot topic,andthe effect of metal(such as Cu,Fe,Ag,Au,Pt,W,V,Pb,Cr,Rh,Co and Ni)ions doping on photocatalytic ac-tivity of Ti O2has been studied widely[14].Howev-er,there wer…  相似文献   

11.
采用EO20PO70EO20(P123)作为模板剂,通过溶胶-凝胶-程序升温溶剂热一步法并经不同时间微波辐射处理,制备了一系列纳米复合材料Ag/TiO2。采用XRD、XPS、TEM、N2吸附-脱附测定和SEM-EDS等测试手段对其组成、结构及形貌等进行表征。结果显示,微波辐射5min制备的Ag/TiO2晶型结构最佳,该产物中Ag以单质形式存在,其比表面积可达100.64m2·g-1,平均孔径约为6.9nm。与未经微波辐射样品相比,其颗粒细小、结构规则、分布均匀、无明显团聚现象。以甲基橙为模型分子,考察经不同时间微波辐射处理的纳米复合材料Ag/TiO2的紫外光催化活性。结果表明,在微波功率为200W,微波时间为5min时获得的Ag/TiO2的催化活性最高,循环使用3次后降解率仍能达到80%以上。  相似文献   

12.
A new electrochemical method to prepare photocatalytic TiO2 thin film was developed, by which the TiO2 was electrodeposited on surface of alumina by AC electrolysis in solution consisting of K2 [TiO(C2O4 )2] and C2H2O4. The deposited TiO2 thin film was primarily characterized by X-ray diffraction (XRD), scanning electronic microscopy (SEM) and energy dispersive spectrum (EDS) methods. The photocatalytic properties of this film were also studied by the photocatalytic degradation of methyl orange. The results show that the TiO2 film electrodeposited by this method is mainly in amorphous and with a little crystalline component mixed anatase and rutile. The surface of the alumina prepared by anodic oxidation is porous and the TiO2 electrodeposited on it is scattered and incompact. TiO2 thin film fixed on the surface of alumina shows photocatalytic activity to the degradation of methyl orange.  相似文献   

13.
溶胶凝胶法制备TiO2薄膜及其润湿性研究   总被引:1,自引:1,他引:0  
采用溶胶凝胶法,于金属基片上构筑TiO2薄膜,通过修饰1H,1H,2H,2H-十七氟癸基三甲氧基硅烷后,薄膜显示疏水性.对TiO2凝胶的热稳定性进行分析,结果显示,在450℃及以上的温度进行热处理,有机成分可被全部除掉.对所制备薄膜的物相组成和显微结构进行表征,并考察热处理温度对薄膜表面形貌及润湿性能的影响,结果表明,热处理温度为550℃时,疏水性能最好,达到超疏水性.  相似文献   

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The SiO2/TiO2 composite powders including mineral tourmaline powders (T/SiO2/TiO2) were prepared from a sol made by a two-step hydrolysis method, using metasilicate ester as precursor. The powders were characterized by scanning electron microscopy (SEM). The photocatalytic activity of the sample was evaluated by the photocatalytic degradation of methyl orange. The effects of heat-treatment on the photocatalytic activity were discussed. It is found that the T/SiO2/TiO2 composite powders show higher photocatalytic activity when including 10% SiO2 and 4% tourmaline. Moreover, the photocatalytic mechanism of tourmaline on the powders was proposed.  相似文献   

16.
Steady TiO2 water-sol was prepared by peptization and the effects of pH value, temperature, concentration of colloid and peptizator on sol were investigated. Laser grain analyzer was used to verify nano-particles in the sol. The photocatalytic degradation ratio and antibacterial property of nano-Ag/TiO2 thin-film on ceramics were used as the main index in addition to XRD analysis. The effect of film layers, embedding Ag^+, annealing temperature and time on the degradation ratio and antibacterial property was studied. The temperature 30-80 ℃, pH 1.2-2.0, concentrations of 0.05-0.3 mol/L sol and 5% HNO3 would be the optimal parameters for the TiO2 water-sol preparation. The nano-Ag/TiO2 film of three layers with 3% AgNO3 embedded and treated at 350℃ for 2 h exhibits good performance. The elementary research on the kinetics of degradation shows that the reactions are on the first order kinetics equation.  相似文献   

17.
The titanium dioxide sols were synthesized with tetrabutyl titanate as precursor, diethanolamine(DEA) as complexing agent , polyethylene glycol (PEG) as organic template. The porous films were prepared by sol-gel method, The structures and morphology of the titanium dioxide porous films were characterized by FE-SEM. The formation mechanism of TiO2 porous films and the relation between the porous structure and oxygen-sensing properties of TiO2 films were studied. Ordered structure was formed by assembling between TiO2 colloid particles and the template molecules. PEG molecules acted on TiO2 colloid particles by hydrogen bond and bridge oxygen. The porous structure was formed after the organic template was decomposed when calcining the films. The diameter, amount and distribution of the pores in the films are related with the content of PEG. The pore diameter increases with increasing of content of PEG and the pore density reaches the maximum at certain content. Oxygen-sensitivity and response speed of porous TiO2 films are improved compared with films without pores. Both the sensitivity and response speed increase with the increasing of pore diameter and pore density. Oxygen-sensitivity reaches 3 order of magnitude at 800 ℃. Its response time from H2/N2 to O2/N2 atmosphere and vice versa is about 0.11 s and 0.12 s respectively. Although the sensitivity and response speed increase, the resistance-temperature properties of porous films are not notably improved with the increasing of the content of PEG.  相似文献   

18.
通过对TiO2多孔膜阳极氧化制备工艺的研究,提出了其成膜机理。实验以硫酸为电解液,以纯钛(TAl)为阳极,铜片为阴极,采用了恒压和恒流2种阳极氧化方式,在纯钛的表面获得TiO2多孔膜。用FESEM观察其孔径分布在100nm~200nm之间,并且随着阳极氧化电压和电流密度的增加,多孔膜的孔径有增大的趋势。最后,讨论了在硫酸电解液中TiO2多孔膜的形成机制。  相似文献   

19.
单分散纳米TiO2光催化剂的水解-溶胶制备法   总被引:18,自引:5,他引:13  
以Ti(SO4)2为原料,在一定温度下直接水解、胶溶、加入晶种、熟化,制备出单分散性、热稳定性良好、平均粒径在22nm左右、比表面积在80m^2/g以上的TiO2纳米微粒。研究了Ti(SO4)2浓度、水解时间及晶种对纳米微粒粒径的影响。对样品进行了TG-DTA,XRD和SEM分析。结果表明:样品经真空冷冻干燥后,TiO2粉体主要为锐钛矿型,且随焙烧时间增加和温度升高,其金红石型含量显著增多,粉体粒径也有一定增大,但在不同的温度区间粒径增长速率有较大的区别。  相似文献   

20.
PANI/Ag-TiO2纳米纤维复合材料的制备及其抗菌性能研究   总被引:2,自引:0,他引:2  
采用水热法制备Ag掺杂量不同的Ag/TiO2纳米复合材料,通过原位聚合法制备PANI/Ag-TiO2纳米纤维复合材料,利用XRD、SEM、FT-IR等检测技术对复合材料的结构进行了表征。研究了光源、Ag掺杂量、不同实验菌种等因素对PANI/Ag-TiO2纳米纤维复合材料抗菌性能的影响。结果表明:在无光照射情况下,PANI/Ag-TiO2纳米纤维复合材料具有良好的抗菌性能,在长波紫外光照射情况下,抗菌性能进一步增强。在浓度1 mg/mL时,在无需光照的情况下对4种实验菌种杀菌率均达到99.99%。  相似文献   

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