负载纳米TiO2薄膜的光催化自清洁陶瓷的制备

采用溶胶-凝胶法制备了负载有纳米TiO2薄膜的自清洁陶瓷,用XRD表征了TiO2的晶体结构和晶粒度.考察了溶胶前躯体浓度和煅烧温度对自清洁陶瓷亲水性和光催化降解甲基橙性能的影响,并通过测试陶瓷片洗刷后的性能考察了薄膜的附着力.结果表明,前躯体浓度越大,TiO2的晶粒度越大;前驱体浓度对薄膜的亲水性能影响不大,但对薄膜的降解性能和附着力影响较大;薄膜的最佳煅烧温度为500℃.     

纳米锐钛矿型TiO2薄膜的制备及分析

采用反应磁控溅射法在玻璃衬底上制备锐钛矿相TiO2薄膜,研究了工艺条件中的氧氩流量比对薄膜润湿角的影响以及溅射气压对薄膜微观结构的影响。对不同氧氩流量比(分别为1/40,1/20,1/10和1/5)时制备的TiO2薄膜进行润湿角测量,润湿角照片显明:氧氩比1/5时薄膜润湿角可减小到8°左右,即提高氧氩比能增强TiO2薄膜的自洁净性能。X射线衍射(XRD)分析表明:当溅射气压降到1.0 Pa时,可以得到锐钛矿型TiO2薄膜晶体,0.5 Pa时的XRD图衍射峰更为明显。用分光光度计测量了TiO2薄膜的紫外吸收光谱,由光谱曲线上光吸收阈值与半导体带隙之间的关系计算出了TiO2薄膜的禁带宽度为3.42 eV,表明TiO2薄膜的吸收边出现了一定的蓝移。根据XRD图谱计算TiO2薄膜的晶粒尺寸,得到的薄膜晶粒尺寸在十几纳米左右,由此说明了TiO2薄膜吸收边发生蓝移的原因;按照锐钛矿相TiO2薄膜XRD图25.3°衍射峰对应的(101)晶面,由Bragg方程计算出其晶面间距为0.3521 nm,表明TiO2薄膜晶体发生了一定的晶格畸变。     

水热法制备稀土掺杂纳米TiO_2薄膜及光催化降解性能研究

以Ti(SO4)2水溶液为前驱物,尿素为沉淀剂,采用水热法在玻璃基片上制备了稀土离子掺杂的TiO2薄膜。以薄膜对紫外光吸收值为指标,考察了水热反应时间、镀膜次数、掺杂稀土离子的种类、掺杂量对紫外光吸收性能的影响,确定了掺杂薄膜最佳制备条件:在1.0mol/L尿素溶液中,温度为160℃,反应10h,镀膜两次,稀土最佳掺杂量为n(La)=0.9%或n(Eu)=1.1%(n为摩尔比),掺镧元素的效果好于掺铕元素。利用X射线衍射仪(XRD)、扫描电子显微镜(SEM)对所制备的TiO2薄膜的相结构及形貌进行了分析和表征,结果表明,所制备的薄膜均匀、致密、无可视缺陷。以甲基橙为光催化降解的探针化合物,探讨了TiO2薄膜光催化降解性能,结果表明,掺杂稀土离子的TiO2薄膜对光催化降解性能远优于未掺杂的TiO2薄膜。     

TiO2纳米管的制备及光电催化分解海水制氢

采用阳极氧化法在钛板表面制备了垂直导向的TiO2纳米管阵列。研究了无机无氟(HCl+H2O2)、无机含氟(HF)和有机乙二醇(EG)三种体系对TiO2纳米管薄膜制备的影响。利用SEM对其形貌进行了表征,通过电化学考察了其光电响应性能。考察了制备的TiO2纳米管薄膜光电催化分解海水制氢性能。结果表明:在EG体系中制备的TiO2纳米管阵列规则有序,有利于光生电子的传输,减小了电子一空穴对的复合,光电催化制氢活性最高。     

氧氮比对真空电弧沉积TiO_(2-x)N_x薄膜结构和性能的影响

采用真空电弧沉积技术在玻璃上制备了N掺杂TiO2复合薄膜。通过X射线电子能谱(XPS)、X射线衍射(XRD)、紫外可见光谱(UV-Vis)等测试技术研究了沉积过程中氧氮比对TiO2-xNx薄膜结构和性能的影响。实验结果表明,经500℃退火后的TiO2-xNx薄膜均为锐钛矿相,N原子在TiO2网络结构中以取代O原子的形式存在。TiO2-xNx复合薄膜在400～800 nm可见光区的透过率达60%,随着氮含量的增加,吸收边发生红移。在可见光下对酸性品红的降解表明TiO2-xNx薄膜具有可见光活性,随氧氮比的降低可见光催化活性逐渐增强。经自然光照射2 h,不同氧氮比制备的TiO2-xNx薄膜对大肠杆菌、金黄葡萄球菌的杀菌率均达99%以上。     

金属离子掺杂TiO2薄膜的光催化性能研究

在TiO2薄膜中掺入杂质离子是改善TiO2薄膜光催化活性的重要方法，不同金属离子的掺杂能不同程度的提高TiO2薄膜的光催化性能，使TiO2薄膜光催化剂在优化降解大气和水中的污染物等方面具有十分广阔的应用前景。本研究对近年来利用各种金属离子掺杂方式提高TiO2薄膜光催化性能的研究现状进行了综述。     

纳米TiO2薄膜的研究

为了对纳米TiO2薄膜做进一步的研究和扩大它的应用范围，介绍了纳米TiO2薄膜特性、主要制备方法和应用现状，最后结合目前纳米TiO2薄膜的研究情况，提出了今后有待解决的问题。     

Fe离子注入二氧化钛复合薄膜制备及光吸收性能研究

采用溶胶凝胶法在石英基体上制备了纯TiO2薄膜,并通过离子注入方法对TiO2薄膜进行Fe掺杂改性以促进TiO2薄膜光吸收边红移,提高其光吸收性能。利用XRD、XPS及UV-vis对不同注入剂量的Fe掺杂TiO2复合薄膜的晶相结构、原子化学态以及光吸收性能进行了表征。XRD测试结果表明,溶胶凝胶法制得的TiO2薄膜为锐钛矿相,经Fe离子注入后,复合TiO2薄膜经退火后锐钛矿相消失,金红石相出现,因为Fe3+离子进入晶胞代替Ti4+,在TiO2基体形成铁的固溶体,结果氧空缺形成促进了TiO2从锐钛矿向金红石的转变;XPS测试结果表明,经过退火Fe在复合TiO2薄膜中以Fe和Fe3O4形式存在,说明Fe离子进入TiO2晶格取代Ti,但Fe及其氧化物晶体峰未在XRD上观测到,说明两者结晶程度不高,以非晶形态存在;通过对溶胶凝胶法制备的TiO2薄膜注入不同剂量Fe的复合薄膜的紫外-可见吸收光谱分析可知,由于复合薄膜中Fe3O4的存在,使复合薄膜紫外-可见光吸收边发生了红移,并随注入剂量增加红移增大,根据红移效果确定Fe的适宜注入剂量为1×1017 cm-2。     

TLM钛合金表面白蛋白涂层的制备及抗凝血性研究

为提高医用钛合金Ti-3Zr-2Sn-3Mo-25Nb的抗凝血性能,首先通过溶胶-凝胶法在其表面制备一层TiO2薄膜,再将该TiO2薄膜活化处理,最后通过静电自组装法将牛血清白蛋白固定在TiO2薄膜表面形成抗凝血涂层。利用X射线衍射仪(XRD)、扫描电子显微镜(SEM)和接触角测试仪研究了该抗凝血涂层的相结构、表面微观形貌和亲水性特征,并通过动态凝血时间法和血小板黏附实验对比研究了白蛋白修饰前后Ti-3Zr-2Sn-3Mo-25Nb合金的抗凝血性能。结果表明,经白蛋白表面修饰处理后,Ti-3Zr-2Sn-3Mo-25Nb合金的抗凝血性能得到了明显的改善。     

液相沉积制备TiO_2/Al颜料及其在自清洁涂料中的应用

以硫酸氧钛和氢氧化钠为主要原料,采用液相沉积法在片状Al粉表面包覆TiO2,制备TiO2/Al颜料,并进一步制得含有该颜料的自清洁涂料。以油酸为污染模拟物,用油酸的分解率作为评价手段,考察反应pH、煅烧温度、涂膜厚度对该涂料自清洁性能的影响。通过XRD仪对颜料结构进行表征,并对颜料的分散性和耐腐蚀性能进行研究。结果表明:在pH为4.5、煅烧温度为600℃条件下TiO2/Al表面的TiO2晶型为锐钛矿型,因而具有最强的自清洁能力。当颜料涂膜厚75μm时,经紫外灯光照3 h后油酸的分解率达到91%。用752S型可见分光光度计于λ=420 nm处分别测得Al粉和TiO2/Al颜料的透光率,来表征其分散性,结果证明Al粉的透光率比TiO2/Al高30%;用浓度0.1 mol/L的HCl溶液进行腐蚀实验,TiO2/Al颜料的耐腐蚀性能显著提高。     

两步机械球磨法制备M/TiO2复合薄膜及光催化性能研究

采用两步机械球磨法制备了M/TiO₂（M = Al、Sn、Zn、Ti）双层复合薄膜,利用光学显微镜和X射线衍射仪分析了涂层的微观结构和相组成,测定了薄膜的光催化性能,研究了过渡层材质以及球磨时间对复合薄膜光催化性能的影响。研究表明,TiO₂粉体在球磨过程中的晶体结构未发生显著变化,保持了良好的光催化活性。金属过渡层Al、Sn以及Zn将显著削弱复合薄膜的光催化活性,Ti是复合薄膜的理想金属过渡层,制备的Ti/TiO₂复合薄膜具有优异的光催化性能。随着第二步球磨时间的延长,Ti/TiO₂复合薄膜的光催化性能逐渐降低,这是由于第二层薄膜表面TiO₂含量降低的原因所致。     

Crystallization Behavior of Anatase Films in Applied Electric Field Heating Process

In this research the TiO2 thin films were prepared by sol-gel dip coating. The crystallization of the films in the applied electric field heating process was thoroughly studied by many technique, differential thermal analysis (DTA), Raman spectroscopy and atomic force microscope (AFM). Furthermore the phase formation, microstructure and photo-catalytic activity of TiO2 film were studied under the condition of an electric field heating-treatment. It is found that the existence of applied electric field promotes the phase transformation from anatase to rutile. Studies on photo-catalytic degradation show that the photo-catalytic activity of TiO2 thin films in an applied electric field is higher.     

Preparation of Ce4+, Sb3+-Codoped TiO2 Films in Electric Field Heating-Treatment

Titania is an important catalytic material for photo-catalytic applications, and the sol-gel process is one of the most appropriate technologies to prepare TiO2 thin films. In the present paper, the Ce4 , Sb3 -codoped TiO2 films were prepared by sol-gel method, which were heat-treated with an applied electric filed. The phase transformation behavior of Ce4 , Sb3 -codoped TiO2 film in the electric field heating-treatment was studied by XRD and AFM. It is found that the crystals were homogeneous and the average crystal size was about 60 nm. Studies of photo-catalytic degradation show that the photo-catalytic activity of Ce4 , Sb3 -codoped TiO2 films heated to 500 ℃ in an applied electric field was higher.     

Effects of Mineral Tourmaline Particles on Photocatalytic Activities of RE/TiO2 Composite Thin Films

The composite TiO2 films containing the mineral tourmaline particles and rare earth elements (T/RE/TiO2 )were prepared by a sol-gel method using Ti( OC4H9 )4 as raw material. The microstructure and forming mechanism of T/RE/TiO2 films were studied by scanning electron microscope (SEM). Effects of tourmaline on the photocatalytic activities of RE/TiO2 were determined by photocatalytic degradation of formaldehyde. The results show that the photocatalytic degradation ratio of formaldehyde increases by 44.2% with the composite films of Ce/TiO2 containing 0.04%tourmaline, more than that with the thin films of Ce/TiO2 under UV irradiation.     

叠层型Cu沉积TiO2复合薄膜的制备及光学性能

真空蒸镀法结合溶胶凝胶法成功地制备Cu-TiO23层复合结构薄膜.运用XRD,SEM,UV-vis等手段进行结构表征和光吸收性能测试.通过模拟可见光下制备样品对亚甲基蓝溶液降解率的变化,评定其光催化活性.结果表明:该法制备的复合结构薄膜,在未热处理时真空蒸镀的金属层为单质Cu.在723 K热处理后,沉积的Cu被氧化主要以Cu2O的形式存在,而TiO2为单一的锐钛矿晶型.823K保温2.0 h热处理后Cu2O进一步被氧化为CuO,同时出现了少量金红石型TiO2.由于Cu2O与CuO均为窄带隙的半导体,在可见光照射下会发生电子由价带向导带的跃迁,因此复合薄膜表现出明显的可见光吸收性能.降解实验的结果则表明:不同温度热处理后的复合薄膜均表现出较高的光催化活性,特别是723K热处理后的复合薄膜样品可见光催化活性最好,在可见光照射5.0 h后对亚甲基蓝溶液降解率接近100%.分析其原因认为,P型的Cu2O和CuO与n型TiO2半导体接触后,在其界面形成了纳米异质结的结合,其p-n结的内建电场抑制了光生载流予的再复合,提高了量子产率,因此使复合薄膜表现出较高的光催化性能.     

Grain Size and Wettability of TiO2/SiO2 Photocatalytic Composite Thin Films

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 TiO2 films and enhance the hydrophilic property of TiO2 films. The super-hydrophilic TiO2/SiO2 photocatalytic composite thin films with the contact angle of 0-° are obtained by the addition of 10%-20% SiO2 in mole fraction.     

Structure and Properties of TiO2-CeO2 Films Deposited on Soda-Lime Silicate Glass Substrates by R.F.Magnetron Sputtering

TiO2-CeO2 films were deposited on soda-lime glass substrates at different ratio of O2 to Ar (0.10, 0.15,0.20) by R. F. magnetron sputtering. The structure, surface composition, UV-visible spectrum of the films were measured by scanning electron microscopy, X-ray diffraction, X-ray photoelectron spectroscopy and spectrometer. The results show that the films are amorphous, and the relative molar ratio of Ce to Ti is higher than that of the target at lower ratio of O2 to Ar. Only tetravalent Ti 4 and Ce 4 ions are present in the films, and the obtained TiO2 -CeO2 films appear good uniformity and high density. The films deposited on the glass can shield ultraviolet light without significant absorption of visible light.     

New Application of Stainless Steel

Several rigid substrates such as stainless steel, titanium alloy, aluminum alloy, nickel foil, silicon, and sodium lime glass have been employed for manufacturing high quality TiO2 films by metal organic chemical vapor deposition （MOCVD）. The as-deposited TiO2 films have been characterized with SEM/EDX and XRD. The photocatalytic properties were investigated by decomposition of aqueous orange Ⅱ. UV VIS photospectrometer was employed to check the absorption characteristics and photocatalytic degradation activity. The results show that films synthesized on metal substrates display higher photoactivities than that on absolute substrates such as silicon and glass. It is found that solar light is an alternative to UV-light used for illumination during photodegradation of orange Ⅱ. TiO2 film on stainless steel substrate was regarded as the best one for photocatalysis.     

Effects of Co-addition of DBS and PEG on Wetting Performance of TiO2 Film

Nanocrystalline anatase TiO2 films with indium tin oxide(ITO) coated glass as the film substrate were fa-bricated through spin-coating technique. The TiO2 pastes were prepared with sodium dodecylbenzenesulfonate(DBS) modified TiO2 nanocrystals, synthesized by sol-hydrothermal processes in advance, together with different amounts of polyethylene glycol(PEG) macrcmolecules. The as-prepared films were mainly characterized by ultraviolet-visible (UV-Vis) spectroscopy, field emission scanning electron microscopy(FE-SEM) and water contact angle(WCA) mea-surement. Effects of the addition of DBS and PEG on the wetting performance of the resulting films and relevant mechanisms were principally investigated. The results show that the as-prepared film displays super-hydrophilic property after co-addition of DBS and PEG although it is not exposed to ultraviolet light prior to the WCA measure-ment. This appealing result is mainly attributed to the produced micro- and nanometer-scale hierarchical surface structure with uniformly dispersed micro papillae. Each papilla was made up of a great number of TiO2 nanoparticles. The possible formation mechanisms related to the DBS amphiphilic property of the characteristic surface were also suggested. Moreover, the resulting film also exhibits considerable durability in the superhydrophilicity, which is very useful for practical application in self-cleaning, anti-fogging and bacteria-resistant fields.