载二氧化钛聚醚醚酮中空纤维膜光催化反应器的制备及性能

以二氧化钛(TiO_2)为光催化剂、聚醚醚酮(PEEK)中空纤维膜为基体,分别采用了溶胶-凝胶法、共混法及化学接枝法3种方法制备PEEK-TiO_2膜光催化反应器。通过扫描电子显微镜、X射线能谱、X射线衍射、热重分析等测试表征方法详细对比了PEEK-TiO_2膜的结构与性能;并以柠檬黄为模型染料测定了PEEK-TiO_2膜光催化反应器的光催化性能。结果表明,溶胶-凝胶法和化学接枝法制备得到的PEEK-TiO_2膜具有完整的表面及截面形貌,TiO_2主要分布在膜的表面,膜的亲水性和渗透性能得到提升。共混法制备得到的PEEK-TiO_2膜内部存在缺陷,TiO_2主要被包埋在树脂基体内部。光催化性能测试表明,溶胶-凝胶法、共混法和化学接枝法制备得到的光催化膜反应器对柠檬黄染料降解效率(5 h)分别为100%,1%和98.63%。重复实验表明,化学接枝法制备得到的PEEK-TiO_2膜反应器具有优异的重用性能,二次实验对柠檬黄的降解效率达到82.71%。因此,化学接枝法是PEEK中空纤维膜固定化负载TiO_2光催化剂的有效方法。     

晶粒尺寸可控的纳米二氧化钛的制备

采用微乳法和溶胶-凝胶法相结合的方法制备纳米二氧化钛,通过改变制备参数可以将纳米二氧化钛的晶粒尺寸控制在6~30 nm之间。采用X射线衍射、透射电镜等表征手段,对不同的制备条件与晶粒尺寸的关系进行研究。通过在可见光下对亚甲基蓝水溶液的降解测试其光催化活性。结果表明:补充结论纳米二氧化钛具有良好的光催化性能。     

人发的无机复制及金纳米粒子的原位合成

以人发为生物模板, 用溶胶-凝胶法对人发的表皮结构进行了复制. 其中以TEOS和水玻璃为前驱体时头发结构未得到复制, 而以钛酸四丁酯为前驱体, 得到二氧化钛微米管, 微米管的外壁由屋顶瓦状排列的多孔二氧化钛层片组成, 类似于头发表皮层结构. 微米管上的纳米孔可以作为纳米反应器原位合成金属纳米粒子. 微米管道、纳米孔与贵金属纳米粒子在这个体系中结合起来, 因此在催化、吸附与分离等领域可能具有潜在的应用前景.     

掺杂二氧化钛薄膜的光催化降解性能的研究

试验采用溶胶-凝胶法制备TiO2薄膜。在掺杂铁元素后,研究其在紫外光光照下对甲基橙及亚甲基兰的光催化降解效果,研究结果表明掺杂一定量的铁元素的二氧化钛薄膜对甲基橙及亚甲基兰有较好的光催化降解效果,在pH=2时效果最好。     

钛酸丁酯溶胶-凝胶法交联改性聚乙烯醇纳米纤维膜的研究

采用静电纺丝技术制备聚乙烯醇纳米纤维膜,结合溶胶-凝胶法制备二氧化钛对纳米纤维膜进行交联改性。分析交联前后材料表面形貌、表面化学基团变化以及耐水性和热性能。研究纳米纤维膜对模型污染物罗丹明B的吸附和光催化降解性能。结果表明:交联改性后材料耐水性显著提高,纤维形貌保持不变,材料表面化学基团无显著变化,材料热分解温度提高。交联改性后的纳米纤维膜材料容易吸附罗丹明B,紫外光照射下材料具有一定的光催化降解性能。     

纳米二氧化钛/硅胶光催化剂的制备与性能研究

采用溶胶 凝胶法在硅胶载体上制备了纳米二氧化钛 ,研究载体表面负载二氧化钛的结构、表面形态及其光催化性能。实验发现 ,包覆在硅胶表面的二氧化钛大小为 2 0～ 30nm ,且分布均匀 ,晶型为锐钛矿相 ,以甲基橙作为降解对象研究所制备样品的光催化性能。     

共掺杂Cu-Ce/TiO_2光催化性能研究

采用溶胶-凝胶法,以钛酸丁酯为前驱体制备了不同Cu-Ce掺杂量的纳米TiO2光催化材料。通过模拟环境室内甲醛气体的降解实验,探讨了不同样品在日光灯和纯可见光下的光催化效果,并采用X射线衍射仪和紫外-可见分光光谱仪对其晶相结构与光学特性进行表征分析。结果表明,Cu-Ce掺杂能明显提高二氧化钛在可见光下的光催化活性,当Cu-Ce掺杂浓度为2.5%时,对甲醛气体的光催化降解效果最佳。     

低温制备光催化纳米二氧化钛研究进展

综述了近年来具有光催化活性的纳米二氧化钛颗粒及薄膜的低温制备研究新进展，按水热法、溶胶-凝胶法及沉淀法分类介绍了纳米二氧化钛的低温制备的反应原理、产物性能及优缺点，评述了二氧化钛在高分子材质上的负载化研究进展，并展望了该领域的研究前景。     

N掺杂TiO2陶瓷膜的制备及其光催化性能研究

采用溶胶-凝胶法制备N掺杂TiO2溶胶,用浸渍-提拉方法将溶胶涂敷在陶瓷膜表面,制备具有抗污染性能的光催化陶瓷膜。光催化与膜分离技术相结合,处理含盐直接耐酸大红4BS染料废水,考察了料液pH值、初始浓度、跨膜压差、膜面流速等因素对含盐染料废水处理效果的影响。结果表明,该复合陶瓷膜对4BS染料的截留率在99%以上,对无机盐的截留率低于1%,光催化膜分离耦合的膜通量较单一膜分离的通量提高90%。     

专利信息

发明名称 中孔纳米二氧化钛的溶胶凝胶低温 制备工艺公 开 号 CN 1322676A 一种中孔纳米二氧化钛的溶胶凝胶低温制备工艺,以钛酸盐和聚乙烯吡咯烷酮（PVP）为原料,在醇和水溶液中发生水解和缩合反应,以酸作催化剂来控制水解反应的速度,获得TiO2/PVP凝胶,然后通过热处理,消除凝胶中的PVP,得到中孔TiO2纳米粉体。本发明的二氧化钛催化剂具有混晶效应,有较高的光催化活。发明名称 一种纳米α-氢氧化镍及制备方法公开号 CN 1322677A 本发明涉及一种纳米级α-氢氧化镍     

Photocatalytic activity of vanadium-doped titania-activated carbon composite film under visible light

A V-doped titania-activated carbon composite film was prepared by a modified sol-gel method under mild condition. X-ray diffraction analysis revealed that the titania was a pure anatase phase. From scanning electron microscopy and N₂ adsorption-desorption measurements, we found that the composite film was porous since it formed a micro-nano structure. The photocatalytic activity of such film was evaluated through degradation of azo-dye Reactive Brilliant Red under visible light, and was compared to commercially available TiO₂, pure titania and vanadium-doped titania films. Results showed that the photocatalytic activity was enhanced a lot. It was due to expansion of the absorption edge by vanadium doping, and the synergistic effect of activated carbon with titania. Furthermore, the hydrophilic property of the as-prepared composite film was superior to other samples.     

非水体系中电沉积方法制备稀土金属La沉积膜

使用尿素-NaBr-KBr-甲酰胺镀液用电沉积方法在硅基体上沉积出含有金属镧的沉积膜,研究了沉积液中甲酰胺的含量和电流密度等工艺参数对沉积膜的形貌和金属La含量的影响．结果表明,在适当的沉积条件下,沉积膜由金属镧及少量氧化镧组成,呈白灰色、均匀、致密、光滑,La的含量（质量分数）达到91．35％;电流密度过低或过高都使沉积膜的表面形态呈现灰黑色、疏松和粗糙．沉积膜中金属镧的含量先随着电流密度的增大而提高,后又降低．镀液中适当含量的甲酰胺使其呈现较好的流动状态,有利于制备高质量的沉积膜．用聚乙烯醇保护膜可以使沉积膜免于氧化．     

多孔TiO2光催化纳米薄膜的制备和微观结构研究

锐钛矿型多孔ＴｉＯ_２纳米薄膜可以从含聚乙二醇（ＰＥＧ）的钛酸盐溶胶前驱体中通过溶胶-凝胶法制备．涂层的形貌,如孔的大小和孔的分布可以通过聚乙二醇的加入量和分子量来控制．当聚乙二醇的加入量和分子量越大,聚乙二醇热分解后在薄膜中产生的气孔就越多和孔径越大．随着ＴｉＯ_２薄膜中气孔孔径和数量的增加,光的散射增强,薄膜的透光率减小．通过扫描电镜（ＳＥＭ）和重量法测定了薄膜的厚度,每镀一次薄膜的厚度增加约为０．０８μｍ．通过Ｘ射线光电子能谱（ＸＰＳ）和红外光谱（ＩＲ）确定了多孔ＴｉＯ_２纳米薄膜中元素的化学组成和表面羟基含量．实验结果表明：薄膜中除含有Ｔｉ、Ｏ元素外,还有一定量来自有机前驱物中未完全燃烧的碳和少量从玻璃表面扩散到薄膜中的Ｎａ和Ｃａ元素;同时发现薄膜表面的羟基含量随聚乙二醇的加入量的增加而增加     

溶胶凝胶法制备ZnO:Ga作为电流扩散层的LED光电性能研究

采用溶胶凝胶法制备了ZnO:Ga(GZO)透明导电薄膜,并用做GaN基LED的电流扩散层。研究表明,GZO薄膜为多晶薄膜,透光率大于80%,粗糙度为Ra 4.6nm,制备的LED的开启电压为2.4V,并成功的点亮LED芯片。     

非晶型超疏水和超亲水TiO2薄膜的制备与表征

通过溶胶-凝胶法, 以载玻片为基底制得非晶型纳米TiO₂薄膜, 用SEM、 XPS、 XRD和接触角测量仪研究了薄膜的微观形貌、 表面元素、 晶型结构及薄膜的疏水性, 用Wenzel、 Cassie 理论对纳米TiO₂薄膜的润湿性进行了理论分析。结果表明, 经紫外光照射16 h后, 薄膜表面由超疏水性变为超亲水性, 接触角接近0°。薄膜表面合适的粗糙度和低表面能材料表面修饰的协同作用使其表现出良好的超疏水性。     

Enhancement of the light extraction efficiency in organic light emitting diodes utilizing a porous alumina film

The light extraction efficiencies of organic light emitting diodes (OLEDs) utilizing various kinds of porous alumina films with different pore diameters were investigated. The OLEDs with the porous alumina film deposited on the glass surface were fabricated to improve their light extraction efficiency. The porous alumina film was fabricated by using a two step anodizing electrochemical procedure. The current densities as functions of the applied voltage do not significantly change, regardless of the existence and the magnitude of the pore diameter in the porous alumina film. The luminance efficiency of the OLEDs increased with increasing pore diameter. The luminance efficiency of the OLEDs utilizing the porous alumina film with a pore diameter of 70 nm was enhanced approximately 9% in comparison with that of the OLEDs without the porous alumina film. These results indicate that highly efficient OLEDs can be fabricated using a porous alumina film with an optimum pore diameter.     

Sol-gel-based, planar waveguide sensor for gaseous iodine

A novel sensor for gaseous iodine has been developed using a combination of sol-gel processing and planar integrated optical waveguiding technologies. The sensing principle is based on the detection of a charge transfer complex formed between iodine and phenyl groups that have been incorporated into a porous, methylated glass film. The glass film was prepared from siloxane precursors by the sol-gel method. Sensors were fabricated by coating the film over a single-mode planar waveguide. Light was coupled into and out of the laminate structure using integral grating couplers, and formation of the charge transfer complex was monitored as attenuated total reflection of the guided wave. The sensor exhibits a linear response to I(2) in the range of 100 ppb to 15 ppm with response and recovery times less than 15 s. The response is selective to 4 ppm iodine in the presence of 10 ppm chlorine and is stable for at least 3 months.     

Ordered porous diamond films fabricated by colloidal crystal templating

We have developed a colloidal crystal templating method for preparation of diamond films with 2D and 3D ordered porous structures. The technological process involved breaks down into (a) impregnation into the pores of silica colloidal crystal (opal) films of detonation nanodiamond (DND) particles from their hydrosol; (b) microwave plasma-enhanced chemical vapor deposition (MWPECVD) regrowth with diamond of pores with high DND filling; (c) Ar(+) ion dry etching of fragments of shells of coalesced diamond crystallites which form in the course of MWPECVD on the surface of the SiO(2) beads making up the outer surface of a film and (d) wet etching of the SiO(2) template in aqueous HF solution. The final samples are either connected to the substrate or free-standing films of various thicknesses having 2D or 3D ordered porous structures. The morphology of the diamond films fabricated by this method replicates the pore network of the opal template. Raman measurements confirm the diamond structure of the synthesized ordered porous material.     

Monolithic bioreactor immobilizing trypsin for high-throughput analysis

A miniaturized trypsin reactor was prepared by coating a trypsin-containing gel on a porous silica monolith. The trypsin-encapsulated gel was prepared by the sol-gel method. The sol-gel reaction was optimized so that the sol solution containing trypsin forms a thin film on the sol-gel monolith. The trypsin was encapsulated into the gel matrix without losing its activity. The silica monolith was fabricated to fit into a 96-well microtiter plate well and could then be easily removed. The trypsin-immobilized monolith was reacted in the 96-well microtiter plate. After the reaction, the monolith was removed, and the enzymatic activity was measured. The large surface area of the monolith enabled the immobilized trypsin to achieve a high catalytic turnover rate. Furthermore, the kinetic parameter of the immobilized trypsin indicates the absence of diffusional limitations. The durability and repeatability of the fabricated trypsin-coated monolith was tested and found to be satisfactory. The encapsulated trypsin exhibits an increased stability even after continuous use compared with that in free solution. Furthermore, this on-plate bioreactor was applicable to the digestion of protein with multiple cleavage sites.     

新型溶胶-凝胶工艺制备La0.5Ca0.5MnO3薄膜及性能分析

鉴于以醇盐为原料溶胶-凝胶制备La0.5Ca0.5MnO3薄膜工艺中存在诸多苛刻因素,本文以无机盐为原料采用溶胶-凝胶工艺在SiO2/Si(100)衬底上制备了La0.5Ca0.5MnO3薄膜.并用XRD、SEM和TEM等分析手段对薄膜进行了表征,通过不同磁场下电阻-温度(R-T)曲线,研究了样品的磁电阻(CMR)效应...