层状四钛酸钾复合物的制备、表征及光催化性能研究

发布时间：2018-06-10 16:00

本文选题：K_2Ti_4O_9 + 光催化　；参考：《南京理工大学》2017年硕士论文

【摘要】：近十几年来,伴随着可持续发展这一主题,全球性环境问题受到越来越多的关注,在众多环境污染治理技术中,以半导体材料为催化剂的非均相光催化反应由于其具有室温条件反应、深度矿化净化、可直接利用太阳光作为光源来活化催化剂并驱动氧化还原反应等种种独特性能,而成为了一种理想的环境污染治理技术。层状K_2Ti_4O_9是目前发现的光催化活性较高的一种半导体层状金属化合物,因其具有独特的层状结构、层板溶胀剥离、层间离子交换等特性,成为很多学者研究的热门材料,并且应用广泛。本论文设计合成了一系列如石墨烯负载、半导体耦合等K_2Ti4O_9复合物,并研究了其可见光催化性能。(1)N-K_2Ti_4O_9/G(石墨烯)复合材料的制备及光催化性能研究。以尿素为氮源,通过焙烧的方法在K_2Ti_4O_9的层间引入N元素,以石墨烯为载体,通过水热处理最后得到N-K_2Ti4O_9/G复合材料。结果表明,石墨烯负载氮掺杂的四钛酸钾孔径变大并且具有更大的比表面积,降解亚甲基蓝和罗丹明B具有较高的可见光催化活性。(2)Ag_3PO_4-TiO_2/K_2Ti_4O_9复合材料的制备及光催化性能研究。以钛酸异丙酯为钛源通过焙烧的方法得到TiO_2/K_2Ti_4O_9复合材料,然后通过一步沉淀法得到Ag_3PO_4-TiO_2/K_2Ti4O_9复合催化剂,通过XRD、XPS、FT-IR、TEM等手段对该复合材料进行表征,结果表明TiO_2包裹在K_2Ti_4O_9的表面,并且TiO_2和Ag_3PO_4的粒径分别为20 nm和3 nm左右。实验结果表明当AgNO_3和TiO_2/K_2Ti_4O_9的投料比为2:1时该复合催化剂活性最高,在可见光下光照该催化剂对亚甲基蓝(MB)、罗丹明B(RhB)和甲基橙(MO)均具有较好的降解性能。(3)Ag_3PO_4/H_2Ti_4O_9纳米片的制备及其光催化性能研究。首先,通过将层状H_2Ti_4O_9在四丁基氢氧化铵溶液中先剥离,然后通过负载Ag3P04将剥离后的纳米片重组,最后得到了H_2Ti_4O_9纳米片负载不同含量的Ag3P04纳米粒子,采用XRD、XPS、FT-IR、TEM等表征手段对复合材料进行了测试,结果该复合催化剂在可见光照射下对亚甲基蓝(MB)和罗丹明(RhB)均具有较好的催化降解效率,并且该复合催化剂有较高催化活性主要归因于剥离后的纳米片具有更大的比表面积和小粒径、高分散的Ag_3PO_4纳米粒子与H_2Ti_4O_9纳米片之间显著的协同效应。
[Abstract]:In recent years, with the theme of sustainable development, global environmental problems have received more and more attention. The heterogeneous photocatalytic reaction with semiconductor materials as catalyst has many unique properties, such as room temperature reaction, deep mineralization purification, direct use of solar light as light source to activate catalyst and drive redox reaction, etc. And has become an ideal environmental pollution control technology. As a kind of semiconductor layered metal compound with high photocatalytic activity found at present, the layered K2Ti4O stack is a kind of semiconductor layered metal compound. Because of its unique layered structure, swelling and stripping of laminates, and ion exchange between layers, it has become a hot material studied by many scholars. And widely used. In this thesis, a series of Ks _ 2Ti _ 4O _ 9 composites, such as graphene supported and semiconductor coupling, have been designed and synthesized, and their visible photocatalytic properties have been studied. N-K2Ti4O9 / G composites were obtained by hydrothermal treatment with urea as nitrogen source and N element as N element in the layer of K2Ti4O\ +\ {9\}\ +\ {9\}\ +\ {9\}\ +\ {}\} _ (9)\%\ +\ { The results show that the graphene supported nitrogen doped potassium tetratitanate has larger pore size and larger specific surface area. The degradation of methylene blue and Rhodamine B have higher visible photocatalytic activity. The preparation and photocatalytic properties of the composite are investigated. Tio _ s _ 2K _ 2Ti _ 4O _ 9 composite was obtained by calcination with isopropyl titanate as titanium source, and then it was characterized by the one-step precipitation method to obtain Ag3PO _ 4-TiO _ 4O _ 9 composite catalyst by means of XRDX / XPS-FT-IRTEM. The results showed that TiO2 was wrapped on the surface of K2Ti4O9. The particle sizes of TiO2 and AgS3PO4 are about 20 nm and 3 nm, respectively. The results show that the composite catalyst has the highest activity when the feed ratio of Agno _ 3 and Tio _ 2 / Ks _ 2TiO _ s _ 9 is 2:1, Under visible light, the catalyst has better degradation performance for methylene blue MBO, Rhodamine Bhh RhB and methyl orange moths. The preparation and photocatalytic properties of the catalyst are studied. First, by stripping the layered H2Ti4O9 in the Ding Ji ammonium hydroxide solution, then by loading the Ag3P04 to recombine the stripped nanoparticles, finally, we get the H2Ti4OS9 nanoparticles loaded with different contents of Ag3P04 nanoparticles. The composite materials were characterized by XRDX XPS FT-IR TEM. The results showed that the composite catalyst had better catalytic degradation efficiency for methylene blue MBB and Rhodamine Rh B) under visible light irradiation. The higher catalytic activity of the composite catalyst is mainly attributed to the larger specific surface area and smaller particle size of the peeled nanoparticles, and the remarkable synergistic effect between the highly dispersed AgSn3PO4 nanoparticles and the H2TiSP-4O9 nanoparticles.
【学位授予单位】：南京理工大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：O643.36;O644.1

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