CeO2论文：纳米CeO_2复合物的制备及光电性质研究

1、 CeO2论文：纳米CeO_2复合物的制备及光电性质研究【中文摘要】YiO2是一种优良的半导体材料,在太阳能电池、光催化、空气净化方面有着广泛的应用。稀土元素具有独特的4f亚层电子结构,与半导体材料复合可以改进其性能。目前报道较多的是关于稀土掺杂半导体材料的光催化性质,对于其电化学性质研究的很少。本文采用溶胶-凝胶法,制备出多种CeO2复合物,采用扫描电子显微镜(SEM)、-射线衍射仪(XRD)、红外光谱仪(FT-IR)、紫外-可见光谱(UV-vis)等对产物的结构和组成进行了表征,探讨了复合物的形成机理,研究了产物的电化学发光性质和光催化性质。论文主要内容如下：1. TiO2/CeO2复合薄

2、膜的制备及其电化学性质研究首先利用溶胶-凝胶法制备TiO2溶胶,然后掺杂一定量的Ce(NO3)3·6H2O,采用浸渍提拉的方法,经过不同的煅烧温度得到TiO2/CeO2复合薄膜。利用SEM、XRD、UV、FTIR等测试手段对他们的形貌、晶型等性质进行表征。同时,通过循环伏安法(CV)对合成薄膜的电化学发光(ECL)性质进行对比研究,考察不同pH的电解质溶液对其ECL结果的影响。研究表明：TiO2/CeO2复合薄膜的电化学发光性能相比较单纯薄膜有很大的提高,不同煅烧温度对于复合薄膜的形貌和电化学性质有较大的影响。结果显示：在200下煅烧1h后,再于450下煅烧1h,所得样品具有较好的E

3、CL性质。2. TiO2/CeO2复合粉末的制备及其电化学性质研究以Ce (NO3) 3·6H2O为铈源,通过氨水沉淀法得到黄色的CeO2粉末。在溶胶-凝胶法制备YiO2溶胶时,加入一定量的上述CeO2粉末,经过干燥、煅烧、研磨以得到淡黄色的TiO2/CeO2复合粉末。利用SEM、XRD等现代分析测试手段对所得的产物进行表征,利用循环伏安法研究TiO2/CeO2复合粉末电化学发光性质。实验研究了不同的扫描范围,不同pH的电解质溶液,以及粘合剂nafion对ECL性质的影响,结果表明：不同扫描范围、不同pH的电解质溶液,所得ECL不同,适当的nafion浓度可以将样品很好地固定在玻碳电

4、极上。对于样品产生的两个峰ECL1与ECL2,通过控制所加电位研究了它们的发光机理。结果表明：ECL1为电化学发光峰,ECL2伴随有化学发光峰。3. CeO2/GO纳米复合物的制备及其光催化性质研究以Ce (NO3)3·6H2O为铈源,通过氨水沉淀法首先得到黄色的Ce02粉末,然后通过混合法制备掺杂氧化石墨烯(GO)的CeO2/GO复合物。产物用扫描电镜、X射线粉末衍射和固体紫外可见光谱进行表征。在太阳光照下测定了产物对亚甲基蓝溶液的光催化降解效果。结果表明：GO可以大大增强CeO2/GO复合物对亚甲基蓝的光催化效果。【英文摘要】TiO2 is an excellent semico

5、nductor material that has a wide applications in solar cell, photocatalysis, and air purification. As well known, rare earth element has a unique 4f sub-layer electronic structure that can improve the performance of semiconductor composites. Recently the photocatalysis of the rare earth doped semico

6、nductor materials has mainly been studied, but their electrochemical properties have rarely been reported.In this paper, various CeO2 composites were prepared by using sol-gel method, and the structure and composition of the products were characterized by Scanning Electron Microscope (SEM), X-ray Di

7、ffraction (XRD), Infrared Spectrometer (FT-IR), and X ultraviolet-visible Spectroscopy (UV-vis). The formation mechanism of the composites was discussed, and the electrochemical luminescence property and photocatalysis of the products were studied.Our main work as follows:1. The preparation and elec

8、trochemical property of TiO2/CeO2 composite filmsFirst, the TiO2 sol-gel prepared by using the sol-gel process was doped with a certain amnount of Ce (NO3) 3·6H2O. Then, the TiO2/CeO2 composite films were prepared by dipping lifting method and calcining. The morphology and crystal structure of

9、films as-obtained were characterized by SEM, XRD, UV and FTIR. The electrochemical luminescence (ECL) of the composite films was studied by cyclic voltammetry (CV), and the effect of the electrolyte solution with different pH on ECL was discussed. The results show that the ECL property of the TiO2/C

10、eO2 composite films has been greatly improved, comparing to the pure films. The calcining temperature affected the morphology and electrochemical property of composite films. When calcinated at 200for 1h and then at 450for 1h, the composite film as-obtained has a excellent ECL property. 2. The prepa

11、ration and electrochemical property of TiO2/CeO2 composite powderWith Ce (NO3) 3·6H2O as cerium source, the CeO2 yellow powder was first obtained through the ammonia precipitation method. Then, the TiO2 sol formed by sol-gel process was added a certain amount of the CeO2 powder. Finally, the Ti

12、O2/CeO2 composite powder was obtained by drying and calcining the sol. The products as-prepared were characterized by SEM and XRD, and their ECL property was studied by cyclic voltammetry. The effect of scanning range, the pH of electrolytic solution and adhesive nafion on ECL was discussed. The res

13、ults show that the different ECL curves was obtained in different scanning range or with different pH solution. With appropriate amount nafion, the powder can be solidly fixed on the surface of glassy carbon electrode. Significantly, the ECL1 and ECL2 peaks produced by TiO2/CeO2 composite powder wer

14、e studied by controlling potential exerted on the work electrode. The result shows that the ECL1 is electrochemical luminescence peak and ECL2 involves some chemiluminescence component.3. The preparation and photocatalysis of CeO2/GO composite powderWith Ce (NO3)3·6H2O as cerium source, the CeO

15、2 yellow powder was first obtained through the ammonia precipitation method. Then, the CeO2/GO composite powder was prepared by mixing graphene oxide and CeO2 powder. The structure and composition of the products were characterized by SEM, XRD and UV-vis. The photocatalytic activity of the CeO2/GO c

16、omposite power was studied by photodegradating organic methylene blue with sun light. The results show that the GO can enhance the photocatalysis of the composite powder.【关键词】CeO2 复合物 制备 电化学发光 光催化【英文关键词】CeO2 Composite Preparation Electrochemical luminescenc photocatalysis【目录】纳米CeO_2复合物的制备及光电性质研究中文摘要

17、5-7ABSTRACT7-8第一章 绪论9-28§1.1 电化学发光研究现状9-161.1.1 电化学发光机制9-141.1.1.1 湮灭机制10-121.1.1.2 共反应机制12-141.1.2 常见ECL体系14-161.1.2.1 无机体系14-151.1.2.2 有机体系15-16§1.2 CeO_2纳米复合材料的研究现状16-18§1.3 本论文的主要研究内容18-20参考文献20-28第二章 TiO_2/CeO_2薄膜的合成及其电化学发光性质研究28-41§2.1 引言28-29§2.2 实验部分29-312.2.1 试剂与仪器2

18、92.2.2 样品的制备29-302.2.3 产物的组成和结构表征302.2.4 产物的电化学性质测试30-31§2.3 结果与表征31-372.3.1 结果与表征31-322.3.2 产物的EDX32-332.3.3 产物的UV与FTIR33-342.3.4 产物的ECL34-37§2.4 本章小结37-38参考文献38-41第三章 TiO_2/CeO_2复合粉末的制备41-58§3.1 引言41-42§3.2 实验部分42-443.2.1 试剂与仪器42-433.2.2 样品的制备433.2.3 产物的组成和结构表征433.2.4 产物的电化学性质测试43-44§3.3 结果与讨论44-533.3.1 产物表征结果44-453.3.2 XRD分析45-463.3.3 TiO_2/CeO_2复合物的电化学性质研究46-53§3.4 本章