摘 要二十一世纪,随着世界经济快速的发展、世界人口急剧的增长和人民生活水平 不断的提高,能源的消耗量也创下了新高,由此导致了世界各国对能源资源的竞争 激烈,生态环境遭受了严重的破坏。光催化作为一项先进的高级氧化技术,采用该 技术处理污水中的生物难降解的有机污染物和空气净化等,在环保领域已经成为了 重要课题受到世界各国研究者的重视。其中,最具应用前景的光催化剂 TiO2 作为典型的代表,其光催化性能得到研究者的高度关注。然而,TiO2 禁带宽度大(Eg = 3。2 eV), 太阳光中只能利用紫外部分,可见光利用率较低。为了解决这个问题,本文以 P25 纳米催化剂为基础,采用窄带半导体 MoS2 对其进行改性,制备了 TiO2/MoS2 纳米 催化剂,经过 SEM、Raman、EDX、XPS 和 DRS 等手段进行表征。结果表明,MoS2 成功负载到 TiO2 的表面,且分布均匀。本文利用 MB 作为目标污染物对复合催化剂 的活性进行考察。结果表明,TiO2/MoS2 经过 90 min 对 MB 光催化降解率高达 86。6%, 而 P25 对 MB 降解率仅为 7。5%。通过实验可知,温度对 TiO2/MoS2 影响不大,因此 它的适用范围较广;此外,在碱性条件下,光催化降解效率较好,因为在碱性条件下发生质子化过程,产生更多具有强氧化性的羟基自由基,光催化效率得到大大提 高。83162
毕业论文关键词:光催化;TiO2;可见光;TiO2/MoS2
Abstract The 21st century, with the rapid development of world economy, the world's population sharp growth and constantly improve people's living standard, the consumption of energy is also hit a new high, the resulting from around the world to the energy resources of the competition is intense, the ecological environment suffered serious damage。 Photocatalysis as a senior advanced oxidation technology, using the technology of sewage biological refractory organic pollutants and air purification and so on, in the field of environmental protection has become an important issue to the attention of the researchers around the world。 Among them, the most application prospect of TiO2 photocatalyst as a typical representative of the photocatalytic performance is the researchers' attention。 However, TiO2 forbidden band width (Eg = 3。2 eV), can only use ultraviolet part of sunlight, the visible light utilization rate is low。 In order to solve this problem, this paper on the basis of P25 nanometer catalyst, using narrow band semiconductor MoS2 for modification, preparation of TiO2/MoS2 nanometer catalyst, through SEM, Raman, EDX, XPS and DRS were characterized。 Results show that MoS2 success load to the surface of TiO2, and evenly distributed。 In this paper, using the MB as the target pollutants of examining the activity of composite catalyst。 The results showed that the TiO2/MoS2 after 90 min for MB photocatalytic degradation rate is as high as 86。6%, and P25 for MB degradation rate is only 7。5%。Through the experiment, the temperature of TiO2/MoS2 impact is not big, so it has a wide applicable scope; In addition, in alkaline conditions, photocatalytic degradation efficiency is better, because the protonation process that occurs in alkaline conditions to produce more hydroxyl radicals with strong oxidizing, photocatalytic efficiency are improved greatly。
Keywords: Light catalysis; TiO2; Visible light; TiO2/MoS2
目 录
第一章 绪 论 1
1。1 研究背景 1
1。2 TiO2 光催化机理 2
1。3 提高 TiO2 光催化性能的研究 3
1。4 MoS2 的性能及其研究进展 5
1。5 TiO2 国内外研究进展以及存在的问题