丝素蛋白/TiO2复合催化剂的制备及其可见光催化性能

通过溶胶-凝胶法制备了不同掺杂量的丝素蛋白/TiO2复合纳米材料,并研究了其可见光催化活性.用粒度分析、X射线衍射(XRD)、紫外-可见漫反射光谱(UV-Vis-DRS)、平带电位、Zeta-电位、元素分析等方法表征了所制备的催化剂样品.结果显示,在可见光照射下,反应2 h时,丝素蛋白/TiO2-400℃的Cr(VI)光催化还原效率达36%,甲酸降解效率达3.4%;相对纯TiO2,丝素蛋白/TiO2的可见光吸收能力均有提高,以丝素蛋白/TiO2-400℃的增幅最大;相对纯TiO2,丝素蛋白/TiO2的平带电位均有不同程度负移,这意味着光生电子有了更强的还原能力;TiO2-400℃、素蛋白/TiO2-300℃、丝素蛋白/TiO2-400℃、丝素蛋白/TiO2-500℃的Zeta-电位值分别为29、31、36、33 mV,说明丝素蛋白/TiO2-400℃在水中形成的溶胶系统分散程度最高.     

仿贝壳自组装纳米复合薄膜的制备及结构表征

利用超分子自组装方法在普通玻璃表面制备了仿贝壳有机 无机复合纳米薄膜.采用X射线衍射仪、傅立叶红外光谱仪、紫外 可见吸收光谱仪、透射电子显微镜对薄膜结构进行了表征.结果表明这种薄膜具有有机 无机有序交替的层状纳米复合结构，聚合前层间距为4.20 nm，聚合后层间距为3.91 nm.无机层由TiO2纳米微粒构成.     

正钛酸胶溶法制纳米TiO2薄膜及性能表征

The Nanometer TiO₂ thin film was prepared by sol method with titanic acid precursor from industrial TiOSO₄ solution. The characters of the sol and the factors affecting sol formation were investigated by ζ electricity potential. The crystalline structure, particle size, appearance shape and photo-catalytic activity were characterized by XRD, SEM, TEM and spectrophotometer. The study show: (1) pH value and HNO₃concentration effected importantly on the forming process and stability of the sol. The thermodynamic condition for forming sol is pH=0.5～1.5. The lower the HNO₃concentration,the more stable the sol. The ζ electricity potential of the sol, with 5% HNO₃as gluing reagent, was up to 48 mV, and shelf life of the sol could more than 10 months. (2) The film, made from the sol and crystallized at 400 ℃, had the characters of anatase structure and crystal size of 18.5 nm by XRD analysis. The SEM imagines show that TiO₂ film was with the characteristics of tight surface structure, The TEM imagine showed the mean particle size is about 20 nm. The photo-degrading test data indicate that the photo-degrading rate to methyl orange solution of 20 mg·L^-1 was more than 84% in 5 hours.     

纳米TiO2薄膜的制备方法

本文对纳米TiO₂薄膜的各种制备方法，包括基于溶胶－凝胶的涂层方法、电沉积、化学气相沉积、物理气相沉积、自组装制膜，以及喷雾热分解等方法的研究进展进行了综述，对不同方法的优缺点进行了比较和评述，对今后TiO₂薄膜制备的研究方法提出了一些建议。     

纳米TiO2/CdSe量子点的制备及其结构表征

用水热方法制备了CdSe量子点(CdSe QDs)并通过溶胶-凝胶法制备了量子点掺杂改性的纳米TiO2复合物。运用多种方法对此复合物进行表征,并对其光催化性能进行研究。结果表明:1在其制备焙烧过程中,CdSe QDs已掺杂进入TiO2纳米颗粒中形成纳米复合物;2 CdSe QDs的引入增强了TiO2的吸光性,改善了TiO2在可见光区的吸光效率;3 TiO2的原始晶体结构在焙烧过程中发生变化,形成了两种晶相的混晶,有利于其光催化活性的改善;此外纳米TiO2复合物的表面电子结构以及吸附性能等对其光催化作用也有协同作用,使其催化性能进一步提高。     

纳米结构TiO2/PS及TiO2空心球的自组装与表征

以TiCl₄的盐酸溶液配制的TiO₂溶胶为前驱体, 以聚苯乙烯微球为载体, 在表面活性剂存在下, 通过逐层自组装技术制备了纳米结构TiO₂/PS及TiO₂空心球. 利用XRD, SEM, TG-DTA等对复合颗粒进行了表征. 研究表明: 纳米结构TiO₂/PS的组成、结构、形貌和粒度可通过溶胶酸度、组装时水解反应温度、煅烧温度、硫酸根的加入量来控制.     

纳米结构TiO2/PS及TiO2空心球的自组装与表征

以TiCl₄的盐酸溶液配制的TiO₂溶胶为前驱体, 以聚苯乙烯微球为载体, 在表面活性剂存在下, 通过逐层自组装技术制备了纳米结构TiO₂/PS及TiO₂空心球. 利用XRD, SEM, TG-DTA等对复合颗粒进行了表征. 研究表明: 纳米结构TiO₂/PS的组成、结构、形貌和粒度可通过溶胶酸度、组装时水解反应温度、煅烧温度、硫酸根的加入量来控制.     

纳米CT成像表征锦纶6中TiO2颗粒分布状况

无机纳米材料与高分子基质共混构成有机-无机复合材料,对其电学、光学和机械性能产生显著影响,因而受到广泛关注.为使其性能得到切实改善,需要使无机纳米材料在高分子基质中均匀分散.对其分散状态的检测传统方法是对材料进行超薄、连续切片后,用透射电子显微镜(TEM)进     

FeNi层状双氢氧化物/TiO2复合光催化剂的制备及其制氢性能

层状双氢氧化物(LDH)的光生电子-空穴对易复合,虽然纳米薄片的结构促进了载流子分离,但其光催化效率仍然较低。我们利用LDH薄片结构的优势,将FeNi LDH和TiO₂通过静电自组装复合,设计制备出新型高效的FeNi LDH/TiO₂复合光催化材料,评价了其光催化分解水产氢性能。对其结构、光催化性能和光电化学等进行了详细表征。结果表明,FeNi LDH的高比表面积、复合物的异质结结构都有利于光生电荷的转移。光催化产氢结果表明,FeNi LDH/TiO₂复合材料的产氢速率(22.6mmol·g^-1·h^-1)分别比纯TiO₂(0.1 mmol·g^-1·h^-1)和FeNi LDH(0.05 mmol·g^-1·h^-1)提高了226和452倍,表明了异质结在提高LDH光催化效率方面的重要作用。     

TiO2-SnO2复合凝胶的结构表征及其吸附与光催化性能研究

采用溶胶-凝胶法制备了TiO2-SnO2复合凝胶,利用XRD、UV、IR谱对其结构进行了表征,研究了复合凝胶的组成对水、乙醇、丙酮、氨水蒸气平衡吸附量的影响,以苯酚溶液为模拟污染物测定了复合凝胶的光催化降解能力.实验结果表明,组成为n(TiO2)∶SnO2=80%∶20%的复合凝胶具有最强的吸附和光催化活性,对水蒸气、乙醇、丙酮气体的吸附以及对苯酚溶液的光催化降解能力均高于其它组成的复合凝胶.     

Carbon Aerogels Synthesizd with Cetyltrimethyl Ammonium Bromide (CTAB) as a Catalyst and its Application for CO2 Capture

A series of carbon aerogels were synthesized by polycondensation of resorcinol and formaldehyde using cetyltrimethyl ammonium bromide (CTAB) as a catalyst. The structure and properties of carbon aerogels were characterized by X‐ray diffraction (XRD), Raman, scanning electron microscope (SEM), Fourier transform infrared spectroscopy (FT‐IR), and N₂ adsorption‐desorption technologies. Besides, the CO₂ capture behavior of carbon aerogels was also investigated. It was found that the amount of CTAB affected the structure and morphology of carbon aerogels, thus influenced the CO₂ adsorption behavior. The sample CA‐125 (the ratio of resorcinol and CTAB is 125) had the highest CO₂ adsorption capacity (63.71 cm³ · g^–1 at 1 bar and 24.14 cm³ · g^–1 at 0.15 bar) at 25 °C. In addition, the higher CO₂ adsorption capacity was ascribed to the higher surface area, pore volume and appropriate pore size, as well as the more defects over carbon aerogels.     

Preparation and Magnetic Properties of Submicron CrO2 Thin Film on Poly-crystal TiO2 Film

The submicron chromium dioxide(CrO₂) thin film was fabricated on a poly-crystal titania(TiO₂) film using Si wafers as substrates by atmospheric pressure chemical vapor deposition(CVD) method. X-Ray diffraction patterns show that the CrO₂ films were pure rutile structure. Scanning electron microscopy(SEM) images indicate that the CrO₂ films consisted of submicron grains with a grain size of 250―750 nm. The magnetic researches reveal that the magnetic easy axis is parallel to the films, and at room temperature, the CrO₂ films show linear magnetoresistance.     

Micelle-induced multiple performance improvement of fluorescent probes for H2S detection

In this paper, two colorimetric and turn-on fluorescent probes N-[2-(2-hydroxy)-ethoxy] ethyl-4-azido-1,8-naphthalimide (SS1) and N-butyl-4-azido-1,8-naphthalimide (SS2) for selective recognition of H₂S were designed and synthesized. The probes were constructed by incorporating an azido group into the naphthalimide fluorophore as a specifical reaction group for sulfide utilizing its reducing property. Once treated with H₂S, the azido groups of the probes were converted to amino groups and the solutions’ color changed from colorless to yellow companied with a strong yellow-green fluorescence. Rapid and sensitive responses of the probes towards H₂S were achieved in the presence of cationic surfactant cetyltrimethyl ammonium bromide (CTAB): the reaction was completed within 10 min in CTAB compared to more than 4 h in buffer solution, and the detection limit decreased from 0.5 μM to 20 nM. High selectivity and good competition of both probes towards H₂S over other 11 ions and 2 reducing agents were realized in CTAB micelle. An overall linear concentration range of 0.05 μM to 1 mM was achieved with the assistance of differently charged surfactants CTAB and sodium dodecyl sulfate (SDS). The probes were applied to rapidly and sensitively detect H₂S levels in fetal bovine serum without any pretreatment of the sample.     

Ag/TiO2中空纳米纤维光催化材料的制备及表征

以棉花纤维为模板制备了银掺杂的TiO₂中空纳米纤维光催化材料, 利用热重分析(TG)、扫描电子显微镜(SEM)、X光电子能谱(XPS)、X射线衍射(XRD)、Zeta电位、紫外-可见光谱(UV-Vis)和傅立叶变换红外光谱(FT-IR)等技术对该材料的形貌、晶体结构、银的状态等特性进行了表征. 以亚甲基蓝(MB)的脱色降解为模型反应, 考察了银掺杂的样品Ag/TiO₂在不同光源下的光催化性能. 结果表明, 所制得的Ag/TiO₂材料保留了棉花纤维的形貌, 且表面带有大量的负电荷|该Ag/TiO₂材料在太阳光条件下的光催化性能显著高于同条件下TiO₂和同材料在紫外光条件下的, 如Ag/TiO₂在太阳光下1.5 h可使MB溶液的脱色降解率在95%以上, 在TiO₂上2.5 h时不足60%, 低于Ag/TiO₂上0.5 h的结果|在紫外光条件下Ag/TiO₂ 3 h时脱色降解率仅为35%. 连续重复使用5次时Ag/TiO₂仍能保证MB溶液的脱色降解率在90%以上|该纤维光催化材料易于离心分离去除、再利用. 因此, 以棉花为模板制备的Ag/TiO₂中空纳米纤维催化材料是一种无能耗、无污染、高活性的绿色环保型光催化材料.     

Preparation and Characterization of Polypyrrole/TiO2 Coaxial Nanocables

Summary: We demonstrate in this communication that large‐scale coaxial nanocables of polypyrrole (PPy)/TiO₂ can be obtained via three steps: (1) synthesis of TiO₂ nanofibers by electrospinning; (2) physical adsorption Fe³⁺ oxidant on the surface of TiO₂ nanofibers; (3) followed by polymerization of pyrrole (from vapor) on the surface of TiO₂ nanofibers. During the synthesis, the PPy formed on TiO₂ nanofibers as a template and formed PPy/TiO₂ coaxial nanocables. TEM image proved that PPy (20 nm thickness) covered the surface of TiO₂ nanofibers. Fourier‐transform infrared (FTIR), X‐ray photoelectron spectra (XPS), and X‐ray diffraction patterns (XRD) characterized the chemical structure of the coaxial nanocables. Surface photovoltage spectroscopy (SPS) revealed the surface properties of the PPy/TiO₂ coaxial nanocables.

TEM image of individual PPy/TiO₂ coaxial nanocable.     

TiO2/SiO2复合材料的制备与表征

以钛酸四丁酯和正硅酸乙酯为原料,采用溶胶凝胶法和水解法相结合,在室温下制备了两种形态的TiO2/SiO2复合材料.采用透射电镜、傅里叶红外光谱、X射线衍射和紫外-可见光谱等测试方法对所得复合材料进行了表征,并对其光催化降解甲基橙溶液的性能进行了研究.结果表明:对TiO2进行表面处理制备的TiO2/SiO2复合材料比以SiO2为载体制备的TiO2/SiO2复合材料在光催化和抗紫外线性能上更优异.     

介孔TiO2-ZnO复合薄膜的制备与表征

以三嵌段聚合物P123为模板剂, 以钛酸异丙酯和二水乙酸锌为无机前驱体, 利用溶胶-凝胶法和旋涂法成功地制备了不同ZnO含量的介孔TiO2-ZnO复合薄膜. 在ZnO前驱体摩尔分数为0~50％范围内获得薄膜质量较高的介孔TiO2-ZnO复合薄膜. 用小角XRD、扫描电子显微镜(SEM)、高分辨透射电子显微镜(HRTEM)、能谱仪(EDS)、紫外-可见吸收光谱(UV-Vis)及X射线光电子能谱(XPS)对所得的复合薄膜进行了表征和分析. EDS和XPS等研究证明介孔薄膜为TiO2和ZnO的复合体系, 且ZnO前驱体含量的增加仍能保持TiO2-ZnO复合薄膜的均匀性. UV-Vis研究结果表明, 介孔复合薄膜的光学带隙宽度为3.45-3.58 eV, 随着ZnO含量的增加, 复合薄膜的紫外吸收蓝移.     

Preparation and Photocatalytic Characterization of Nanoporous TiO2

Nanoporous TiO2 photocatalysts were prepared by use of controlled drying method with surfactants. The surface area and porous properties are dependent on the chain length of incorporated surfactant cation. The TiO2 materials prepared in the presence of surfactant molecules during the gel formation exhibit much higher photocatalytic activity than that prepared in the absence of surfactants.     

PS/TiO2复合纳米微球的制备和结构表征

无机纳米微粒具有特殊的物理化学性能 ,近年来在摩擦学领域中受到越来越多的重视 .由于无机纳米微粒难以分散于润滑基础油中 ,故其作为润滑材料主要用作聚合物填料和润滑脂添加剂 .为了改善其在基础油中的分散性 ,需要对无机纳米微粒进行表面改性 ,制备成有机无机复合纳米微粒 ,从而使它们能够用作润滑油添加剂 .目前有机小分子表面修饰无机纳米微粒的摩擦学性能已有报导 [1－ 3],但是聚合物修饰无机纳米微粒的研究较少 ,并且大多是采用高分子（如 PVK,PVA等）直接包埋的方法 ,用这种方法制得的微粒 ,粒径差别较大,性能不太稳定 .　　本…