【作者】 王俊哲；

【导师】 姚合宝；

【作者基本信息】 西北大学 ， 凝聚态物理， 2011， 硕士

【摘要】 Ti02作为稳定的宽禁带半导体(乓=3.2eV)在许多领域有着重要的作用,尤其是它的光催化性能近几年成为研究的热门。但作为光催化剂,Ti02存在着其自身的不足,概括起来主要是：对可见光不吸收和光生电子-空穴复合率高。很多研究通过对Ti02掺杂来解决上述问题,有一些研究通过掺Ce来改善Ti02的光催化性能,但大部分是通过溶胶-凝胶法制备的。溶胶-凝胶法制备的Ti02薄膜由于与衬底具有较差的附着力,大大影响了Ti02的实际应用。基于此,我们采用磁控溅射法制备了掺Ce的Ti02薄膜,并对薄膜进行了表征分析,发现Ce掺杂扩展了氧化钛薄膜对可见光的吸收范围并且展示了更好的光催化活性。磁控溅射法的优点在于：膜层致密、均匀,与基底附着力好,而且已经实现了产业化。本文利用了磁控溅射法在石英薄膜上室温条件下生长了掺Ce二氧化钛纳米薄膜,并对薄膜的结构、性能、光催化性进行了研究。此外还研究了薄膜的一些参数对薄膜光催化性能的影响,并对N、Ce共掺Ti02做了一些探究。第一章首先介绍了Ti02和Ce02的结构、性质及用途,然后对掺Ce二氧化钛薄膜的研究进展做了介绍,并阐述了课题的研究内容。第二章主要介绍了实验设备及对薄膜的测试表征的仪器。我们利用磁控溅射法,采用自制靶材,在石英玻璃上生长不同掺杂比的掺Ce二氧化钛薄膜。并通过X射线衍射仪、紫外-可见分光光度计、X射线光电子能谱仪、荧光光谱仪等分析薄膜的结构、光学性能及光催化特性。第三章首先介绍了掺杂靶材的制作工艺,并在磁控溅射系统内完成了掺Ce氧化钛薄膜的制备。对薄膜XRD分析测试发现,薄膜的XRD谱是Ti02、Ce02和Ce203晶型结构的综合体现。不同掺Ce比的氧化钛薄膜的透过率测试结果显示,随着掺铈量的增大,薄膜逐渐出现红移,薄膜的禁带宽度由3.29eV减小到2.67eV,对可见光吸收增强。薄膜XPS分析表明,部分Ti4+被还原成了Ti3+,而大部分的Ce4+转化成了Ce3+。通过对薄膜的光致发光谱分析,我们发现掺杂后的薄膜没有显示出Ti02的特征发光峰,但光强度减弱。最后通过对不同掺Ce比Ti02薄膜光催化性能研究,我们发现掺Ce比为5%的掺杂薄膜显示出了较好的光催化能力。第四章研究了薄膜的制备参数,如膜厚、退火温度等对薄膜光吸收及其光催化性的影响。我们发现,影响Ti02薄膜光催化的参数不是单一的,是各个因素相互作用的综合体现。第五章总结了本文的工作。并对掺Ce二氧化钛薄膜的研究与应用进行了展望。更多还原

【Abstract】 As a stable wide band gap semiconductor, TiO2 play an important role in many areas, especially its photocatalytic has become a hot research in recent years. But as a photocatalyst, TiO2 has its own limitation which summed up is:don’t absorb visible light and high electron-hole recombination rate. To solve the problem, some studies improve the photocatalytic of TiO2 by Ce-doped, but it’s fabricated mostly by the sol-gel method. But the TiO2 film made by sol-gel have poor adhesion with the substrate, affected the practical application of TiO2 greatly. Thinking of this, we fabricate the Ce-doped TiO2 by magnetron sputtering. We found that the Ce-doped titania films extend the range of visible light absorption and shows a better photocatalytic activity though the characterized and test.Magnetron sputtering method has the advantage as follows:films fabricated by it are compact, uniform, good adhesion with the substrate and has achieved industrialization.In this paper, we prepared the Ce-doped TiO2 film at room temperature by the magnetron sputtering, and studied the structure, properties, and photocatalytic of films. In addition, some parameters of the film which affect the photocatalytic also studied. Finally we made some inquiry to N, Ce co-doped TiO2.The first chapter introduces the structure、properties and uses of TiO2 and CeO2, then the research progress of Ce-doped TiO2 film was introduced. Finally we elaborated the content of research.The second chapter describes the experimental equipment and the testing equipment. Firstly, we made the TiO2 target with different ratio of CeO2, then we prepared the Ce-doped TiO2 film on quartz glass by the magnetron sputtering. By the X-ray diffraction, UV-visible spectrophotometer, X-ray photoelectron spectroscopy, fluorescence spectroscopy and other analysis equipment, we studied the structure, optical properties and photocatalytic of different films.The third chapter introduces production process of the doping target firstly, then we prepared the Ce-doped TiO2 film in the magnetron sputtering system. XRD analysis showed that the XRD spectrum of doping films are structure of the integrated embodiment for TiO2, CeO2 and Ce2O3 crystal. The transmittance of TiO2 film with different Ce-doped show that:with the increase of cerium-doped, films’Eg appeared red-shift from the 3.29eV decreases to 2.67eV, the visible light absorption was enhanced. XPS analysis of 5% Ce-doped films showed that some of the Ti4+ converted to Ti3+, and most of the Ce4+ converted into Ce3+. Though the photoluminescence spectroscopy, we found that the Ce-doped TiO2 films don’t show the new emission peak, but the light intensity decreased. Finally, we test the photocatalytic properties of Ce-doped TiO2 films with different cerium ratio, the results showed that the 5% Ce-doped TiO2 film show a best photocatalytic ability.In the chapter 4, we studied how the thin film parameters such as, thickness and annealing temperature affect the optical absorption and photocatalytic of TiO2 film. At last we found that the parameters which affect the photocatalytic of TiO2 film is not single, it’s a comprehensive result of various factors interact.In the chapter 5, all the work was summarized. Finally the future research and application of Ce-doped TiO2 film were discussed.更多还原