溶胶-凝胶法制备SiO2-TiO2纳米复合薄膜紫外光处理的研究

采用溶胶－凝胶技术,结合二步水解法分别在单晶硅片、石英玻璃和K9玻璃上制备SiO2-TiO2纳米复合薄膜,采用高压汞灯对其进行紫外光处理,分别用AFM、椭偏仪、FTIR、UV－Vis分光光度计以及XRD对凝胶膜紫外光处理前后的光学性能和结构进行研究,并与传统的热处理进行比较与分析。研究表明,紫外光处理是实现凝胶膜低温致密化的有效方法之一,其致密化的机理不同于传统的热处理,主要是通过紫外高能光子诱导复合薄膜网络结构的原子中的电子激发,导致原子化学键的断裂,进而产生结构重组而致密化。     

溶胶-凝胶法制备SiO2-TiO2复合薄膜的抗刻蚀能力研究

采用Ｓｏｌ－Ｇｅｌ工艺制备ＳｉＯ２－ＴｉＯ２复合薄膜,研究在不同温度下薄膜对ＨＦ缓冲溶液的刻蚀能力。薄膜经８００℃热处理的刻速率是２００℃热处理的１／１０００倍,利用这种差异,在薄膜上用激光进行致密化处理,从而形成所需的图形。     

VO2薄膜的主要制备工艺参数研究

通过正交试验设计对制备ＶＯ２薄膜过程中的部分影响因素（膜厚，最终热处理温度和热处理保温时间）进行了分析研究。ＶＯ２薄膜由无机溶胶－凝胶法制备Ｖ２Ｏ５凝胶膜经真空热处理而成。试验结果表明，ＶＯ２薄膜的最终电学性能明显受到膜厚、热处理温度和保温时间的影响。其中以热处理温度的影响最为显著。当真空度为３Ｐａ、升温速率为２℃／ｍｉｎ时，在试验参数范围内（真空热处理温度３４０￣５００℃，保温时间４０￣２４０ｍ     

溶胶—凝胶法制备TiO2—SiO2复合薄膜的研究

采用溶胶－凝胶方法在单晶Ｓｉ基片上制备了ＴｉＯ２－ＳｉＯ２复合薄膜，研究了溶剂、ｐＨ值对先体溶液成胶时间的作用，溶液的浓度、甩胶时的旋转速度、涂覆层数以及热处理温度对薄膜厚度、光学性能的影响。薄膜的折射率随温度增大，其主要贡献来自于薄膜中结构的变化。并测量了薄膜的Ｉ－Ｖ、Ｃ－ｆ特性，由于薄膜中的热击穿效应而使得ＴｉＯ２含量较高的薄膜２的Ｉ－Ｖ呈非线性变化。     

医用NiTi合金表面溶胶-凝胶法制备TiO2-SiO2薄膜

采用溶胶－凝胶法在ＮｉＴｉ形状记忆合金表面制备了ＴｉＯ_２－ＳｉＯ_２复合薄膜,在提高医用ＮｉＴｉ合金的抗腐蚀性方面,收到了显著的效果．运用电化学方法对不同组成的ＴｉＯ_２－ＳｉＯ_２薄膜在模拟体液中的腐蚀行为进行了研究,结果表明,随薄膜中 Ｔｉ／Ｓｉ比的增加,ＴｉＯ_２－ＳｉＯ_２薄膜的抗腐蚀性增强．划痕试验表明 ＴｉＯ_２－ＳｉＯ_２（Ｔｉ／Ｓｉ＝４：１）膜与ＮｉＴｉ合金基体具有较高的界面结合强度．用原子力显微镜（ＡＦＭ）对ＴｉＯ_２－ＳｉＯ_２薄膜的表面形貌及表面粗糙度进行观察和分析,解释并讨论了ＴｉＯ_２－ＳｉＯ_２薄膜的配方组成与其抗腐蚀性的关系,ＳｉＯ_２含量较少时,薄膜结构致密,膜层均匀平滑,且膜基结合力好,作为医用ＮｉＴｉ合金的表面保护层,可以使其耐腐蚀性有显著提高．     

TiO2薄膜的液相沉积法制备及其性能表征

采用液相沉积法（LPD）制备了透明TiO2薄膜,并研究了所制薄膜的形貌、结构和在紫外光照射下亲水性能的变化．结果表明,用此法制得的TiO₂薄膜较为均匀致密,热处理前后的薄膜具有相似的亲水性能,在紫外光照射下亲水性能都有提高．热处理后的薄膜在紫外光照射一定时间后可与水完全润湿．     

纳米La2O3／TiO2复合薄膜的制备及光催化性能研究

采用溶胶-凝胶法在陶瓷基体上制备了纳米La2O3／TiO2复合薄膜。利用XRD研究了La2O3不同复合量对纳米TiO2晶型转化的影响，利用SEM研究了Al2O3底膜对La2O3／TiO2复合薄膜形貌的影响，利用亚甲基兰溶液紫外光降解实验研究了La2O3／TiO2复合薄膜的光催化性能．结果表明：复合0．5％（物质的量）La2O3的TiO2干凝胶经850℃煅烧后仍为锐钛矿（64％（质量分数））占主导的混晶结构，平均粒径在10nm左右；当Al2O3底膜和La2O3／TiO2复合薄膜的厚度分别为4层和3层时，经850℃煅烧后，复合薄膜致密且无微裂纹出现，而且具有佳的光催化性能．     

一种制备r—Fe2O3薄膜的新方法

采用一种简单的新工艺分别在硅片和氧化铝陶瓷基片上制备了ｒ－Ｆｅ２Ｏ３薄膜。该工艺分３步完成：首先利用Ｆｅ（ＮＯ２）３酒精溶液通过浸渍涂布工艺制备ａ－Ｆｅ２Ｏ３薄膜，其次ａ－Ｆｅ２Ｏ３薄膜在氢气流中、３２０￣３５０℃之间热处理３０ｍｉｎ被还原为Ｆｅ３Ｏ４薄膜，最后Ｆｅ３Ｏ４薄膜在空气中２５０℃左右热处理３０ｍｉｎ被氧化为ｒ－Ｆｅ２Ｏ３薄膜。ＸＲＤ和ＳＥＭ分析结果表明该ｒ－Ｆｅ２Ｏ３薄膜呈尖晶石物相和     

医用NiTi合金表面溶胶-凝胶法制备TiO2-SiO2薄膜

采用溶胶－凝胶法在ＮiTi形状记忆合金表面制备了ＴiO2-SiO2复合薄膜,在提高医用ＮiTi合金的抗腐蚀性方面,收到了显著的效果,运用电化学方法对不同组成的ＴiO2-SiO2薄膜的抗腐蚀性增强,划痕试验一ＴiO2-SiO2(Ti/Si=4:1)膜与ＮiTi合金基体具有较高的界面结合强度,用原子力显微镜（ＡＦＭ）对ＴiO2-SiO2薄膜的表面形貌及表面粗糙度进行观察和分析,解释并讨论了TiO2-SiO2薄膜的配方组成与其抗腐蚀的关系,ＳiO２含量较少时,薄膜结构致密,膜层均匀平滑,且膜基结合力,作为医用ＮiTi合金的表面保护层,可以使其耐腐蚀性有显著提高。     

TiO2-SiO2双组分膜结构与光催化性能的研究

采用溶胶-凝胶法制备了不同Si／Ti比的TiO2-SiO2双组分膜．用紫外光照射亚甲基蓝的分解实验比较薄膜的光催化性能．通过XRD、FTIR、HRTEM、FE—SEM、AFM以及UV—VS—NIR分光光度计等分析手段对薄膜的结构和光学性能进行了表征．结果表明：适量SiO2的引入，显著提高了TiO2薄膜的光催化活性，Si／Ti比为0．2时薄膜的光催化活性为最佳．SiO2引入TiO2薄膜后，生成了Ti—O—Si玻璃相和无定形SiO2，这两种物相聚集在TiO2晶界周围，有效地阻止了TiO2的晶粒长大，提高了锐钛矿相向金红石相的转变温度，使复合薄膜经过500℃热处理后，只有锐钛矿相存在，有利于薄膜的光催化活性的提高．     

非晶ZrO2-SiO2系薄膜及微细图形的制备

采用溶胶－凝胶与化学修饰相结合的方法制备了ZrO2-SiO2系薄膜，研究了这种凝胶薄膜的FT－IR光谱特性及随紫外线照射时的变化，发现在1600－1400cm^-1之间有一些与含锆螯合物相关的峰，这些峰值随紫外线照射而减弱，表明这些螯合物发生分解，伴随着螯合物的分解，薄膜的乙醇中的溶解能力也发生变化，利用这特性，紫外光通过掩膜照射凝胶薄膜，用有机溶剂溶洗后，获得凝胶薄膜的微细图形，再进行热处理，消除薄膜中的有机物就可得到非晶质ZrO2-SiO2系薄膜的微细图形。     

用于紫外光电导探测器的TiO2薄膜研究

采用直流反应磁控溅射的方法,制备了TiO2薄膜。用X射线衍射,原子力显微镜(AFM)和紫外-可见光分光光度计分别测试了TiO2薄膜的晶体结构、表面形貌及其紫外-可见光吸收谱,采用C／TiO2／ITO三层结构制备了TiO2光电导型紫外探测器,研究了它的光响应。初步实验结果表明：TiO2薄膜在4W的紫光灯辐射下,光电流可达2．1mA,10min的辐射时间内,光电流基本保持稳定,可见TiO2薄膜对紫外光有较高的灵敏度和稳定性,可作为一种良好的紫外光探测材料。     

Rapid erasing of wettability patterns based on TiO2-PDMS composite films

TiO₂-polydimethylsiloxane (TiO₂-PDMS) composite films are prepared using the sol–gel method from a Ti(OBu)₄–benzoylacetone solution containing PDMS. The prepared films are cured by irradiation with ultraviolet (UV) light. Structural changes in the films after UV irradiation are confirmed by UV–vis absorption experiments, which show that an absorption band characteristic of the benzoylacetonate chelate rings disappears. This finding is ascribed to structural changes associated with the dissociation of the chelate rings. The IR spectra of the thin films exhibit a broad absorption band after UV irradiation, indicating that a Ti–O–Ti network forms in the thin film. Contact angles are measured for the TiO₂-PDMS thin films, showing wettability conversion from hydrophobic to superhydrophilic states by irradiation with oxygen plasma for 1 s. This phenomenon is explained by XPS experiments which reveal that the number of carbon atoms decreases, whereas the number of oxygen atoms increases on the surface of the TiO₂-PDMS composite films. Finally, hydrophobic–superhydrophilic patterns are fabricated based on a patterned TiO₂-PDMS composite film. The film displays a rapid change to superhydrophilicity over the whole film surface upon plasma irradiation for 1 s, which means that the wettability patterns are rapidly erasable.     

Fabrication of SiO<Subscript>2</Subscript>/TiO<Subscript>2</Subscript> double layer thin films with self-cleaning and photocatalytic properties

Transparent antireflective SiO₂/TiO₂ double layer thin films were prepared using a sol–gel method and deposited on glass substrate by spin coating technique. Thin films were characterized using XRD, FE-SEM, AFM, UV–Vis spectroscopy and water contact angle measurements. XRD analysis reveals that the existence of pure anatase phase TiO₂ crystallites in the thin films. FE-SEM analysis confirms the homogeneous dispersion of TiO₂ on SiO₂ layer. Water contact angle on the thin films was measured by a contact angle analyzer under UV light irradiation. The photocatalytic performance of the TiO₂ and SiO₂/TiO₂ thin films was studied by the degradation of methylene blue under UV irradiation. The effect of an intermediate SiO₂ layer on the photocatalytic performance of TiO₂ thin films was examined. SiO₂/TiO₂ double layer thin films showed enhanced photocatalytic activity towards methylene blue dye.     

Ag/TiO2薄膜结构和光催化性能研究

采用溶胶-凝胶技术制备了Ag掺杂的TiO2薄膜.用XRD、氮吸附法、UV-VIS-NIR分光光度计以及XPS对Ag掺杂后TiO2薄膜结构的变化进行了分析;用分光光学法通过在紫外光照下分解亚甲基蓝的实验比较了TiO2薄膜与Ag/TiO2薄膜的光催化性能.结果发现,掺杂适量的Ag有助于TiO2薄膜光催化氧化性能的提高,原因在于:（1）Ag通过引入耗尽层提高了TiO2的电荷分离能力,并吸引空穴向薄膜表面移动,结果使薄膜表面空穴的浓度提高,薄膜光催化效率提高;（2）Ag减小了TiO2粒子的粒径,使TiO2禁带宽度增大,薄膜光催化氧化的能力提高;（3）Ag掺杂后,TiO2薄膜表面对-OH基和水的吸附增加,使光照后TiO2薄膜表面活性自由基·OH的浓度增加,空穴向薄膜所吸附物质的转移能力提高.     

Photoinduced hydrophobic surface of graphene oxide thin films

Graphene oxide (GO) thin films were deposited on transparent conducting oxide substrates and glass slides by spin coating method at room temperature. The wettability of GO thin films before and after ultraviolet (UV) irradiation was characterized with water contact angles, which increased from 27.3° to 57.6° after 3 h of irradiation, indicating a photo-induced hydrophobic surface. The UV-vis absorption spectra, Raman spectroscopy, X-ray photoelectron spectroscopy, and conductivity measurements of GO films before and after UV irradiation were taken to study the mechanism of photoinduced hydrophobic surface of GO thin films. It is demonstrated that the photoinduced hydrophobic surface is ascribed to the elimination of oxygen-containing functional groups on GO molecules. This work provides a simple strategy to control the wettability properties of GO thin films by UV irradiation.     

溶胶—凝胶法制备YBCO超导薄膜微细图形

以甲醇为溶剂,以醋酸铜、醋酸钇和醋酸钡为起始原料,二乙烯三胺、三氟乙酸、丙烯酸为添加剂,采用溶胶-凝胶法制备了具有紫外感光性的YBCO溶胶及其凝胶薄膜,其紫外吸收峰在250nm附近,对应于铜络合物的电子跃迁吸收,随着紫外光的照射,其峰值逐渐降低,凝胶在有机溶剂中的溶解性也发生变化,显示了凝胶薄膜的紫外感光性.基于这一特性,本文提出了一种YBCO 超导薄膜图形制备新方法,即利用凝胶薄膜自身的紫外感光性,使紫外光通过掩模照射薄膜,然后在甲醇中溶洗,进一步热处理,得到了YBCO超导薄膜图形.结果表明,图形化的YBCO薄膜具有较强的c轴取向,超导转变温度T_C达到92K.     

Effects of addition of supramolecular assembly on the anatase nanocrystalline precipitation of sol-gel derived SiO2-TiO2 coating films by hot-water treatment

Effects of the addition of a supramolecular assembly of cetyltrimethylammonium bromide in SiO2-TiO2 gel films on the formation of anatase type TiO2 nanocrystals with hot-water treatment were investigated. Anatase nanocrystals were formed in the whole SiO2-TiO2 gel films with the addition of cetyltrimethylammonium bromide by the treatment, whereas the nanocrystals were formed only on the film surface in the case of gel films without cetyltrimethylammonium bromide. Cetyltrimethylammonium bromide molecules in the SiO2-TiO2 gel films were completely removed by the hot-water treatment and the following UV irradiation. In the usual procedure for preparation of porous materials, the removal of template molecular assemblies required high temperature treatment over 400 degrees C. In this system, all the processes were performed at temperatures less than 100 degrees C. Additionally, the porous structure produced by the removal of micellar assembly allowed anatase nanocrystals to be formed inside the films. Therefore, the method presented in this work provides us with the novel photocatalyst coatings of porous membrane with highly-dispersed TiO2 nanocrystals via low temperature process.     

Ag/TiO2薄膜结构和光催化性能研究

采用溶胶-凝胶技术制备了Ag掺杂的TiO₂薄膜.用XRD、氮吸附法、UV-VIS-NIR分光光度计以及XPS对Ag掺杂后TiO₂薄膜结构的变化进行了分析;用分光光学法通过在紫外光照下分解亚甲基蓝的实验比较了TiO₂薄膜与Ag/TiO₂薄膜的光催化性能.结果发现,掺杂适量的Ag有助于TiO₂薄膜光催化氧化性能的提高,原因在于:（1）Ag通过引入耗尽层提高了TiO₂的电荷分离能力,并吸引空穴向薄膜表面移动,结果使薄膜表面空穴的浓度提高,薄膜光催化效率提高;（2）Ag减小了TiO₂粒子的粒径,使TiO₂禁带宽度增大,薄膜光催化氧化的能力提高;（3）Ag掺杂后,TiO₂薄膜表面对-OH基和水的吸附增加,使光照后TiO₂薄膜表面活性自由基·OH的浓度增加,空穴向薄膜所吸附物质的转移能力提高.