摘要利用光催化剂，能将污染物矿化，并且能够让太阳光能转化为氢能，这些优点使得光催化剂成为能源及环境等领域的研究重点。由于TiO2的禁带宽度大，只能被紫外光激发，开发新型可见光光催化剂成为研究热点。铋系半导体催化剂由于能被可见光激发，光催化性能优异而备受关注。其中卤氧化铋具有独特的层状结构，优异的光催化活性。但BiOCl的禁宽较大，不能很好地利用太阳光。研究发现，富氧型卤氧铋的禁带宽度窄，能被可见光活化。本文要采用水热法制备富氧型卤氧铋（Bi12O17Cl2）。实验中通过改变氯源、pH与反应温度，得到了组成不一样的富氧型氯氧铋。通过XRD、SEM、TEM和UV-vis对产物的结构与形貌，组成进行了表征，结果表明，氯源、pH与反应温度明显影响产物组成。最后，研究了所制备的光催化剂在可见光激发下，催化降解罗丹明B的活性，结果发现，不同组成的光催化剂，其光催化性能不一样。其中，纯Bi12O17Cl2的禁宽约为2。1eV，在可见光下的催化活性优于BiOCl。73533

毕业论文关键词  光催化  水热法  富氧型卤氧铋   可见光

毕业设计说明书外文摘要

Title    Synthesis and properties of oxygen-rich bismuth oxyhalides                     

Abstract Photocatalytic reaction can make pollutants mineralization,and transfer solar energy to hydrogen energy。These advantages make photocatalysts become the key point in the energy and environment research area。 TiO2 has wide band gap,it only inspired by UV light,So developing new type visible light photocatalysts becomes a hot topic。Bismuth-based semiconductor photocatalysts can be inspired by solar visible light,possess good photocatalytic performance,as a consequence,they own worldwide attention。bismuth oxyhalides have unique layer structrues as well as excellent photocatalystic activity。But bismuth oxychloride owns wide band gap,it only uses little of solar energy。Studies have shown that oxygen-rich bismuth oxyhalides possess narrow band gap,they can be activate under visible light。In this thesis,preparing oxygen-rich bismuth oxyhalides (Bi12O17Cl2) according to hydrothermal method。Changing the source of chlorine,pH,and reaction temperature in the experiment to acquire different composition of oxygen-rich bismuth oxychloride。Utilizing X-ray powder diffraction(XRD),Scanning electron microscopy(SEM),Transmission electron microscopy(TEM) and UV-diffuse reflectance spectroscopy(DRS) to characterize the structure,morphology and composition of samples。The results show that the chlorine source,pH,and reaction temperature influence sample’s component a lot。Finally we research photocatalysts’ activity by degradating Rhodamine B(RhB) under solar visible light spectrum, the results turn out samples with different composition have different photocatalystic property。Pure Bi12O17Cl2 is estimated to 2。1eV,which is better than BiOCl in making use of solar visible light。   

Keywords  Photocatalysis  Hydrothermal method  Oxygen-rich bismuth oxyhalides  Visible light 

目   次

1 引言 1

1。1 光催化剂的研究意义 1

1。2 一些铋系光催化剂 1

1。2。1 铋系金属氧化物催化剂 1

1。2。2 BiOX（X=Cl、Br、I）光催化剂