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1、重庆大学本科学生毕业设计（论文）氮掺杂钙钛矿复合氧化物的合成及催化性能 学 生：李涯皓 学 号：20076857 指导教师：高文亮 副教授 专 业：材料化学重庆大学化学化工学院二O一一年六月Graduation Design (Thesis) of Chongqing UniversityStudy on Synthesis and Photocatalytic Performance of N-doped perovskite oxidesStudy Undergraduate: Li YahaoSupervisor: Prof. Gao WenliangMajor: Material Ch
2、emistryChemistry and Chemical Engineering CollegeChongqing UniversityJune 2011重庆大学本科学生毕业设计（论文） 中文摘要摘 要随着全球环境问题和能源问题的不断加剧，以及对清洁能源和可再生能源的开发的迫切需要，使得对太阳能的利用备受关注。其中，能够有效利用太阳能的可见光光催化剂成为了研究热点。钙钛矿型复合氧化物由其高光催化活性、高稳定性及高环境友好性而被视为研发可见光光催化剂的重要材料。而对钙钛矿氧化物进行氮掺杂，在O位掺入N离子，能够有效的减小其禁带宽度，进而延展其光响应域至可见光区，使其获得可见光光催化活性。本论文
3、通过溶胶-凝胶法合成了钙钛矿型复合氧化物Nd1-xSrxMnO3，通过其对甲基橙在紫外光照射下的光催化降解研究催化剂组成及溶液条件对催化活性的影响，随后在通入NH3、不同温度条件下通过高温焙烧法对Nd1-xSrxMnO3进行了氮掺杂，并研究了其可见光催化性能并对其进行了贵金属改性。结果表明，Nd1-xSrxMnO3复合氧化物在紫外光照射下具有一定的光催化活性，并且其催化活性随着Sr掺杂量的提高而提高。但NdMnO3的钙钛矿型结构会随着Sr掺杂量的提高而逐渐被破坏。与此同时，当溶液pH=2时，催化剂达到其最大光催化活性。故Nd0.7Sr0.3MnO3在保有钙钛矿结构的同时具有最高的催化活性。其在
4、pH=2，光照30min的条件下对40ppm的甲基橙溶液的催化降解率达到了80.3%。在500下进行氮掺杂的N-Nd0.7Sr0.3MnO3复合氧化物具有最高的可见光催化活性，pH=2，可见光光照30min的条件下，对40ppm的甲基橙溶液的催化降解率达到了79.4%，成功的获得可见光光催化剂。进一步对其进行贵金属Ag负载后，催化剂在苯乙烯氧化体系中获得了较高的苯乙烯转化率及环氧苯乙烷选择性，当负载比达到4%时，苯乙烯的转化率和环氧苯乙烷的选择性达到最高，分别为26.4%和61.2%。关键词：溶胶-凝胶法，钙钛矿，氮掺杂，可见光光催化，苯乙烯环氧化32重庆大学本科学生毕业设计（论文） ABSR
5、ACTAbstractWith the global environmental problems and the energy problems increased, as well as the eager needs of the clean and reproducible energy of the world, the use of the solar energy attracted many peoples attention. Within them, the visible-light responses Photocatalysts which can use the s
6、olar energy effectively become the research hot spot. The high photo activity, high stability and high environmental friendliness of Perovskite oxides make it to be one of the promising materials of developing visible-light response Photocatalysts. And after nitrogen (N) doping, mixing N ion into ox
7、ygen (O) position, one can effectively decrease the length of perovskite oxides band gap, it means the greaten of its light respond area, thus makes it become visible-light sensitive photocatalysts.This article prepared perovskite type oxides Nd1-xSrxMnO3 via sol-gal method, and then we researched t
8、he relationship between its component and the solvent conditions with its photocatalytic activity through the degradation of Methyl orange, which added the catalyst, under ultraviolet irradiation. After nitrogen doping to the catalyst via calcinations at different temperature in NH3 atmosphere, we e
9、xplored its photocatalytic activity and then made precious metals Modification towards it. The result shows that perovskite type photocatalyst Nd1-xSrxMnO3 have obvious photo activity under ultraviolet irradiation and with the increased of Sr existed in the compound, its activity increased. However,
10、 adding Sr into the oxide will change its structure. And under pH 2, the catalyst gains the highest photo activity. Thus Nd0.7Sr0.3MnO3 has the highest activity while remain its perovskite structure. The degradation of 40ppm Methyl orange at pH 2 reached 80.3% after ultraviolet irradiation for 30 mi
11、n.The N-doping Nd0.7Sr0.3MnO3 which calcined at 500 has the highest visible-light photoactivity. The degradation of 40ppm Methyl orange at pH 2 reached 79.4% after visible-light irradiation for 30 min. We have successfully developed a visible-light responses photocatalyst. Moreover, the catalyst gai
12、ns High styrene conversion and selectivity of styrene oxide in styrene oxidation system after loaded with Ag. When the load ratio reaches 4%, the styrene conversion and selectivity of styrene oxide reached the top, are 26.4% and 61.2% respectively.Keywords：Sol-gel, Perovskite, N-doping, Visible-ligh
13、t Photocatalysts, Styrene epoxidation.重庆大学本科学生毕业设计（论文） 目录目 录摘 要IAbstractII1绪 论11.1钙钛矿复合氧化物的结构特征11.1.1理想的钙钛矿结构11.1.2类钙钛矿结构21.2钙钛矿复合氧化物的应用31.3光催化简介31.3.1光催化研究背景和现状31.3.2半导体光催化机理41.3.3光催化材料的发展51.4影响ABO3型复合氧化物光催化活性的因素61.4.1B位离子61.4.2A位离子71.4.3掺杂71.4.4粒径81.5钙钛矿型复合氧化物的制备方法91.5.1高温固相法91.5.2溶胶-凝胶法91.5.3共沉淀法
14、101.5.4水热法101.5.5燃烧法101.5.6机械混合法101.6氮掺杂对钙钛矿型氧化物的催化性能影响111.6.1氮掺杂可见光响应的机理111.6.2对氮掺杂化合物催化性能的改进111.7苯乙烯环氧化121.8课题研究目的122实验部分142.1仪器与试剂142.1.1实验药品及其规格142.1.2实验仪器及其规格142.2Nd1-xSrxMnO3粉体的合成152.3Nd1-xSrxMnO3粉体的氮掺杂152.4Ag负载N-Nd1-xSrxMnO3制备方法162.5结构表征与催化剂性能检测162.5.1XRD衍射图谱162.5.2紫外光催化活性172.5.3溶液pH值对催化剂催化效率的影响172.5.4可见光催化活性182.5.5光催化氧化苯乙烯183结果与讨论193.1Nd1-xSrxMnO3的结构表征193.2Nd1-xSrxMnO3的紫外光催化活性193.3溶液pH值对催化剂催化活性的影响203.3.1甲基橙溶液浓度和吸光度的关系曲线203.3.2不同pH值对催化活性的影响223.4N-Nd1-xSrxMnO3的可见光催化活性243.5Ag负载N掺杂Nd1-xSrxMnO3的可见光催化氧化活性254结论与展望264.1结论264.2展望26致谢27参考文献28重庆大学本科学生毕业设计（
