ZnO基复合材料的制备、发光及光催化性能研究

发布时间：2018-03-19 03:10

本文选题：光催化　切入点：半导体　出处：《吉林师范大学》2015年硕士论文　论文类型：学位论文

【摘要】：近年来,随着环境保护意识逐渐深入人心,寻找最佳治理工业三废的方法迫在眉睫,光催化法是近年来发展起来的治理工业污水的有效方法,其中Zn O半导体材料就是一种理想的降解工业废水的光催化剂,但由于其量子产率低,光谱响应范围窄等关键问题没有解决严重地限制了其应用与发展。本论文将小尺寸的金属银、钯和金纳米颗粒与半导体Zn O复合形成Ag-Zn O、Pd-Zn O与Au-Zn O复合材料,利用贵金属纳米颗粒作为电子传递介质,同时发挥Zn O半导体的稳定性能、小尺寸效应、紫外光响应等优点,从而提高Zn O的催化性能。通过改变反应条件制备出一系列高稳定性、高催化活性的Zn O基复合材料,实现其催化太阳光降解工业废水中的有机污染物;研究贵金属的掺杂量、分散度以及反应温度等因素对样品发光性质和光催化性能的影响,制备出活性最强的催化剂;探索催化机理,为设计此类催化剂奠定理论及实验基础。取得的主要研究成果如下:1.通过溶剂热法制备出Zn O纳米粒子,XRD、TEM、SEM、UV-vis等表征结果显示样品具有良好的纯度和结晶度,在波长为380nm和550nm附近出现两处明显的光质发光峰(PL),且在太阳光下对染料罗丹明B(Rh B)有催化降解作用。2.通过溶剂热法制备出Ag-Zn O核壳结构,制得的Ag-Zn O具有很好的结晶度和分散度,与纯氧化锌相比,复合材料的PL发光峰有所下降,对染料Rh B的催化降解能力增强。3.通过溶剂热法制备出Pd-Zn O微纳米复合材料,得到的样品为六方状孔隙结构,Pd纳米粒子均匀的分散在氧化锌表面及孔隙内。样品纯度较高,结晶性能良好,发光性能和催化性能都有一定改变。4.通过水热法制备出蜂窝状与多孔柱状Au-Zn O异质结构,它们均具有良好的纯度和结晶性能,两种样品的PL吸收峰都比Zn O降低,对Rh B的催化活性大大提高,由于蜂窝状样品的金含量和表面积较高,所以具有最高的催化活性。5.分别对三种复合材料的光催化机理进行了探究,给出了可能的机理示意图。
[Abstract]:In recent years, with the awareness of environmental protection becoming more and more popular, it is urgent to find the best method to treat industrial waste water. Photocatalytic method is an effective method to treat industrial sewage developed in recent years. Among them, Zno semiconductor material is an ideal photocatalyst for the degradation of industrial wastewater, but because of its low quantum yield, The narrow range of spectral response has not been solved, which seriously limits its application and development. In this paper, small size silver, palladium and gold nanoparticles are combined with semiconductor Zno to form Ag-Zn / Pd-Zn / O composites. Using noble metal nanoparticles as electron transfer medium, the stability of Zn O semiconductor, small size effect, ultraviolet light response and so on are given full play. In order to improve the catalytic performance of Zno, a series of Zn-O matrix composites with high stability and high catalytic activity were prepared by changing the reaction conditions, which can catalyze the degradation of organic pollutants in industrial wastewater by solar irradiation. The effects of dispersion and reaction temperature on the luminescence properties and photocatalytic properties of the samples were used to prepare the most active catalysts, and the catalytic mechanism was explored. The main results obtained are as follows: 1. ZnO nanoparticles XRDX (TEMSEMN) UV-vis have been prepared by solvothermal method. The results show that the samples have good purity and crystallinity. There are two obvious photoluminescence peaks around 380 nm and 550 nm, and the photoluminescence peak is catalytic degradation of Rhodamine BhB under solar light. 2. The core-shell structure of Ag-Zn O is prepared by solvothermal method. Compared with pure zinc oxide, the PL luminescence peak of the Ag-Zn O / O composite decreased, and the catalytic degradation ability of the dye Rh B was enhanced by .3.The Pd-Zn O micronanocomposites were prepared by solvothermal method. The obtained samples are hexagonal pore structure Pd nanoparticles uniformly dispersed on the surface and pores of zinc oxide. The samples are of high purity and good crystallinity. The photoluminescence and catalytic properties have been changed to a certain extent. 4. Honeycomb and porous columnar Au-Zn O heterostructures were prepared by hydrothermal method. Both of them have good purity and crystallinity. The PL absorption peaks of the two kinds of samples are lower than that of Zno. The catalytic activity of Rh B was greatly improved. Because of the high gold content and surface area of honeycomb samples, the photocatalytic activity of three kinds of composite materials was investigated, and the possible mechanism schematic diagram was given.
【学位授予单位】：吉林师范大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TB33;O643.36

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