纳米二氧化钛薄膜的制备及光致发光研究

采用溶胶-凝胶法制备纳米二氧化钛(TiO2)薄膜,扫描电镜观察薄膜比较均匀,成膜性好,通过X射线电子能谱(EDS)分析了薄膜成分.X射线衍射(XRD)分析表明纳米TiO2薄膜呈现锐钛矿和金红石晶型.光致发光(PL)谱结果表明,荧光峰对应着不同的发光中心,且相对体相TiO2的理论值有明显的蓝移,有很好的荧光特性.     

纳米TiO2薄膜的制备及其光催化性能研究

采用溶胶-凝胶(Sol-gel)法在玻璃衬底上制备了纳米TiO2薄膜.采用X射线衍射仪(XRD)、紫外可见一光谱(UV/vis)和原子力显微镜(AFM)对纳米TiO2进行表征.结果表明,经300～700℃退火得到的TiO2粉体呈锐钛矿相,经800℃退火得到了锐钛矿相与金红石相的混合晶相,经900℃退火完全转化为金红石相.薄膜表面粒子分布均匀,表面平均粗糙度为1.54nm,该薄膜具有较高的光催化活性,可直接用于光催化降解有机物等领域,具有广阔的应用前景.     

纳米TiO2薄膜光催化剂的制备及性能研究

以钛酸四丁酯作为前驱体,用溶胶一凝胶法,在玻璃载体上煅烧制备了纳米TiO2薄膜光催化剂,利用扫描电子显微镜（SEM）、X射线衍射（XRD）等表征技术研究了TiO2薄膜的形貌和特性,其光催化性能用4支20W紫外石英杀菌灯照射TiO2薄膜分解亚甲基兰染料溶液表征,结果表明,该催化剂具有锐钛班红石混合晶相和纳米花状结构,纳米TiO2薄膜的光催化能力随着镀膜层数的增加而增加。     

溶胶-凝胶法制备ZnO薄膜及其性能研究

使用溶胶-凝胶法在P型Si(100)衬底上成功地制备了具有c轴择优取向性和高可见光透射率的多晶ZnO薄膜.通过XRD、SEM以及PL光谱等分析,表明:所制备的是结晶良好的ZnO薄膜,表面均匀致密,薄膜晶粒尺寸大约在15～60 nm,颗粒平均直径大约为38nm.由透射谱可知,制备的ZnO薄膜在可见光区域内薄膜的平均透射率在85%以上;由光致发光谱可知,室温下可观察到显著的紫外光发射,说明具有较好的光学性质.     

TiO2纳米薄膜的微结构控制

通过有机酸修饰的水基sol-gel法,分别制备了由层状、针形和球形纳米粒子构成的纳米二氧化钛薄膜,采用SEM、XRD、红外光谱进行了表征。研究发现,调节水解过程中钛酸四丁酯:醋酸的摩尔比,可以控制薄膜的微结构,并对其机理进行了分析。该方法可以应用于sol-gel法制备其他纳米薄膜过程中的材料微结构控制。     

掺杂TiO2的纳米多孔SiO2薄膜的制备及性能研究

采用溶胶-凝胶法、分子模板法及旋转涂覆法在硅衬底上制备掺杂TiO2的SiO2薄膜，并采用差热分析（DSC-TGA）、红外吸收光谱（FTIR）、X射线衍射、小角衍射（SAXS）、原子力显微镜（AFM）、台阶仪（Atomic-Profiler）以及纸擦拭法（paper-wiping method）和胶带剥离法（adhesive tpe-stripping method）对薄膜的性能进行了分析与表征，结果表明，薄膜的最佳热处理温度为400℃，所制备的掺杂TiO2的SiO2薄膜为多孔结构的无定形态，具有较好的机械性能，平均孔径随着膜层的增加而减小，一层膜和两层膜的平均孔径分别为87.4nm和62.8nm，厚度分别为538.7nm和1032.3nm。     

锐钛矿型TiO2纳米棒薄膜的溶胶-凝胶法制备研究

以钛酸丁酯Ti（OC₄H₉）₄、冰醋酸、去离子水和聚乙二醇（PEG）1000为原料,采用溶胶-凝胶法和旋转涂膜工艺,在玻璃衬底上制备出锐钛矿型TiO₂纳米棒。利用X射线衍射仪（XRD）、SEM和紫外可见光谱（UV/Vis）对TiO₂纳米棒薄膜进行了表征。结果表明,实验制备的TiO₂纳米棒为锐钛矿晶型,在TiO₂反应体系中,胶体粒子在加热过程中偶联在一起,1h后形成了TiO₂纳米棒,其直径为30～50nm,长度为100～200nm。同时,在42mL钛的胶体溶液中添加0.30g PEG（1000）后,纳米TiO₂薄膜的可见光透射峰值降低,TiO₂薄膜表面孔径为20～50nm。     

Zn2SiO4：Mn光致发光薄膜的溶胶-凝胶法制备及发光性质的研究

以乙酸锌、氯化锰、无水乙醇、正硅酸为主要原料,用溶胶-凝胶浸渍提拉法在石英片上制得Zn2SiO4：Mn薄膜前驱体,经高温煅烧获得到Zn2SiO4：Mn荧光薄膜,荧光分析其发光性能。     

溶胶-凝胶法制备纳米TiO2

用溶胶 -凝胶法制备纳米TiO2 粉晶。用X射线粉末衍射 (XRD)对不同温度热处理的系列粉末进行了研究 ,结果表明用溶胶 -凝胶法制备的TiO2 纳米晶其晶型转变温度与凝胶时间有关     

Sol-Gel法制备TiO2/PVP纳米复合材料薄膜及性能研究

以钛酸丁酯和聚乙烯吡咯烷酮（ＰＶＰ）为原料,采用ｓｏｌ－ｇｅｌ法制备了ＴｉＯ２／ＰＶＰ纳米复合材料,以原子力显微镜（ＡＦＭ）和红外光谱告示测试方法分别研究了薄膜的表面形貌和材料的结构。结果表明,薄膜表面非常光滑,高度差公为２～５ｎｍ左右,在波数１０９５ｃｍ＾－１处在吸收谱带是Ｔｉ－Ｏ的非对称伸缩振动所产生;同时研究了ＴｉＯ２／ＰＶＰ的介电常数和光致变色性能。     

二氧化钛纳米晶的制备及其光致发光的研究

以Ti（SO4）2为前驱体,采用沉淀法制备了二氧化钛纳米晶,通过X射线衍射（XRD）、透射电子显微镜（TEM）和光致发光（PL）光谱对微晶进行表征。研究表明,制备的TiO2纳米晶呈类球形颗粒且分散性好,平均粒径最小约为4nm,热处理温度升高到750℃时,样品仍为单一的锐钛矿相;PL谱分析表明,室温下,用高于带隙的能量激发,在370～550nm范围内纳米TiO2粒子呈现出强而宽的发光带,分别对应于价带和导带间的电子跃迁以及表面态的发光;另外发现随焙烧温度升高,粒径增大的同时,发光峰的强度呈无规则变化,分析可能与表面态和晶粒内部缺陷的数量有关。     

Preparation and properties of ZnO thin films deposited by sol-gel technique

Zinc oxide (ZnO) thin films were deposited on (100) Si substrates by sol-gel technique. Zinc acetate was used as the precursor material. The effect of different annealing atmospheres and annealing temperatures on composition, structural and optical properties of ZnO thin films was investigated by using Fourier transform infrared spectroscopy, X-ray diffraction, atomic force microscopy and photoluminescence (PL), respectively. At an annealing temperature of 400°C in N₂ for 2 h, dried gel films were propitious to undergo structural relaxation and grow ZnO grains. ZnO thin film annealed at 400°C in N₂ for 2 h exhibited the optimal structure and PL property, and the grain size and the lattice constants of the film were calculated (41.6 nm, a = 3.253 ? and c = 5.210 ?). Moreover, a green emission around 495 nm was observed in the PL spectra owing to the oxygen vacancies located at the surface of ZnO grains. With increasing annealing temperature, both the amount of the grown ZnO and the specific surface area of the grains decrease, which jointly weaken the green emission. Translated from Journal of Lanzhou University (Natural Science), 2006, 42(1): 67–71 [译自: 兰州大学学报 (自然科学版)]     

Low-temperature preparation and characterization of iron-ion doped titania thin films

Iron-ion doped titania thin films with an anatase phase were successfully synthesized in this study using the high-pressure crystallization (HPC) process. The crystallization temperature of Fe(3+)-doped TiO(2) thin films was markedly reduced to be as low as 125 degrees C. The films prepared via the HPC process have a more uniform microstructure and smaller grain sizes than the films prepared via the atmospheric-pressure annealing process. The films prepared via both processes were found to have photocatalytic properties under visible light. The films prepared via the HPC process exhibited enhanced photocatalytic activities in comparison with the films annealed via the conventional process. Increasing the annealing temperature in the HPC process resulted in an improvement in the photocatalytic properties because of an increase in the crystallinity of the prepared films. The HPC process was demonstrated to be a potential method for synthesizing visible-light driven titania thin films with enhanced photocatalytic activities at low temperatures.     

射频磁控溅射制备掺Al的纳米Si-SiO2复合薄膜及其光致发光特性

采用射频磁控技术和退火处理制备掺Al的纳米Si-SiO2复合薄膜.通过X射线衍射(XRD)、X射线光电子能谱(XPS)和傅里叶变换红外光谱(FTIR)表征了薄膜的结构,组分和成键情况.掺Al在SiO2中造成氧空位,使薄膜光致发光强度增强,并出现新的发光峰.退火温度对掺Al薄膜的光致发光的峰位和峰强有较大影响.     

SiOx薄膜的制备及发光特性研究

本论文采用双离子束溅射沉积技术制备了非晶的SiOx薄膜，XPS的测试表明Si是以单原子或低价氧化物的形态存在于薄膜内；在波长为240nm紫外光的激发下，室温及1000℃退火后SiOx薄膜的PL谱图显示样品中存在峰位分别处于320nm，410nm，560nm，630nm四个相互分离的峰，其发光机制分别为来自中性氧空位缺陷（≡Si—O—O—Si≡）、双配位硅悬挂键（O-Si-O）、非桥氧空位中心以及其他缺陷所形成的发光中心。     

溶胶-凝胶法制备ZnFe2O4纳米薄膜及其光电催化性能研究

用溶胶-凝胶工艺在导电玻璃上制备出纳米ZnFe2O4薄膜,用X射线衍射仪、扫描电镜对膜的粒径、物相进行了表征,对不同层数的薄膜进行了光电催化性能测试.薄膜对甲基橙溶液的降解结果表明:随着ZnFe2O4薄膜层数的增多,对甲基橙的降解率先增大后减小,且以3层的ZnFe2O4膜片效果最好.当外加正向偏压时,薄膜的光催化性能有一定提高,且随着偏压增大而呈波动性增强.同时,薄膜与极板间的距离对薄膜的光电催化活性也有较大影响.     

Pb1-xCaxTiO3薄膜制备与微观形态表征

采用溶胶凝胶法（s01-gel）在si（100）衬底上制备了掺钙钛酸铅薄膜。利用DTA-TGA考察不同钙掺杂量对晶化温度的影响；用X射线衍射技术（XRD）研究了钙的不同掺杂量对钛酸铅薄膜的结构的影响；同时用原子力电子显微镜（AFM）对薄膜的表面形貌进行研究考察掺钙对钛酸铅薄膜形貌的影响。     

An important factor for controlling the photoreactivity of titania: O-deficiency of anatase thin films

Oxygen deficient (O-deficient) anatase thin films with high photoreactivity under UV-light irradiation were fabricated by post-annealing partially nitrided anatase thin films, prepared by heat-treatment of precursor films involving a Ti complex of EDTA on an FTO glass substrate at 500 °C for 30 min in an Ar gas flow, in air at 500 °C for 5–30 min. The anatase structure of the transparent thin films was characterized by using XRD and Raman spectra. The O/Ti peak area ratio determined by using XPS of the anatase film having the highest photoreactivity, which was evaluated according to the decoloration rate of methylene blue in an aqueous solution, was 1.5. The photoreactivity of the film was 2.1 times higher than that prepared by using the sol–gel method, with an O/Ti ratio of 1.7. The thin film with the highest photoreactivity indicated the smallest refractive index, 1.99.     

Ge掺杂二氧化钛复合薄膜制备及光吸收性能研究

采用磁控溅射和溶胶-凝胶两种方法在石英基体上制备了纯TiO2薄膜,并通过离子注入及溶胶掺杂方法分别对TiO2薄膜进行Ge掺杂改性。利用XRD、XPS及UV-Vis对两种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。结果表明,磁控溅射法制得TiO2薄膜为锐钛矿相,Ge离子注入引起复合薄膜的锐钛矿相消失,且该相600℃退火后并未得到恢复;经过退火后Ge在磁控溅射TiO2薄膜中以Ge单质存在。溶胶-凝胶法Ge掺杂复合薄膜中存在锐钛矿相TiO2和Ge晶相,Ge在薄膜表面以Ge和GeO2形式存在。两种掺杂方法制得的复合薄膜紫外-可见光吸收边均发生了红移。