摘要目前,能源危机与环境污染问题日益加剧,传统光催化剂只在紫外光范围内有响应,催化效率低、光量子产率低、能源利用率低等难克服的技术性难题制约着光催化技术的发展,开发高效的可见光催化剂成为发展光催化技术的唯一必经之路。论文以制备高效率的铁酸铋-石墨烯复合可见光催化剂为目标,采用Hummers’氧化法制备出氧化石墨,再采用简单易控的一步水热法制备了石墨烯、纯铁酸铋及铁酸铋-石墨烯复合光催化剂。采用XRD,SEM及Raman分析法对上述材料进行表征,确定其晶形为钙钛矿,并观察其形貌。
以亚甲基蓝为模型污染物,考察并比对铁酸铋及铁酸铋-石墨烯复合光催化剂在可见光照射下的光催化性能。研究了石墨烯负载量、催化剂投加量以及污染物初始浓度对光催化性能的影响。结果表明,石墨烯的加入可以提高铁酸铋对MB的光催化性能,且随着石墨烯负载量的增加,光催化效率提高,这主要是由于石墨烯可以有效地促进光生电子和空穴的分离,加上石墨烯较大的比表面积对其吸附性能的改善,使得铁酸铋-石墨烯复合材料的可见光光催化性能有较大提高。5653
关键词:石墨烯 铁酸铋-石墨烯 可见光 光催化
毕业设计说明书(论文)外文摘要
Title Preparation of BiFeO3-graphene composite visible light photocatalyst and its photocatalytic performance under visible light irradiation.
Abstract
Nowadays, environmental pollution and energy shortage problems becomes more and more serious.Traditional photocatalyst only has reaction under UV-light,its low catalytic efficiency, photons productivity and availablility of energy make the visible light photocatalysis hard to develop.So empolding new high efficiency visible light photocatalyst is the only way wo can go. Graphite oxide were prepared from natural graphite by hummers,, grapheme and BiFeO3-Graphene composite visible light photocatalyst were synthesized via a facile hydrothermal process.The as-prepared samples were characterized by X-ray diffraction, scanning electron microscopy and Raman.
The photocatalytic activity of the as-prepared samples were evaluated by the degration of MB.The effect of catalyst dosage ,the initial concentration of pollutants and the graphene content on photoactivity was investigated.It can be concluded that the presence of graphene can accelerate the separation of photogenerated electrons and hole,and the large surface of graphene can improve its adsorption performence,which significantly facilitate the photoactivity of catalyst under visible light.
Keywords Graphene, BiFeO3-Graphene, Visible light, Photocatalysis
目次
1 绪论 5
1.1 可见光催化技术 5
1.2 石墨烯及石墨烯复合光催化材料 6
1.3 石墨烯及石墨烯复合光催化材料的制备与表征 7
1.3.1 石墨烯的制备 7
1.3.2 石墨烯复合光催化材料的制备 8
1.3.3石墨烯复合光催化材料的形成机理 9
1.4 本课题研究的内容 9
2 实验试剂,仪器及表征和分析方法 10
2.1 主要试剂 10
2.2 主要仪器设备 10
2.3 表征方法 10
2.4 光催化性能的研究方法 11
3 石墨烯及石墨烯复合光催化材料的制备与表征 11
3.1 石墨烯的制备 11
3.1.1 预氧化石墨 11
3.1.2 再氧化石墨 11
3.1.3 透析袋的预处理 12
3.2 铁酸铋及铁酸铋-石墨烯复合材料的制备 12
3.2.1铁酸铋的制备 13 石墨烯复合光催化材料的制备及性能研究:http://www.youerw.com/huaxue/lunwen_2775.html