光催化复合材料的研制.doc

毕业设计说明书中文摘要

    锡酸铋Bi2Sn2O7（BSO）是一种新型半导体光催化材料，具有价廉、无毒、化学性质稳定等优点，但单一相的BSO光催化活性低。本文通过高温固相法首次制备出不同氮化碳（g-C3N4）含量的锡酸铋/氮化碳（BSO/g-C3N4）复合光催化剂。利用XRD、TEM、SEM、XPS、UV-vis分别对样品的晶型、组成和形貌等性能进行了表征，并以亚甲基蓝溶液作为模拟污染物，通过亚甲基蓝溶液在可见光下的降解来评价光催化活性的大小。实验结果表明与g-C3N4复合之后的BSO其可见光响应区变宽，光催化活性明显增强。并且g-C3N4复质量分数为60%时复合样品的结晶形态最好，光催化效率最高。这可能是由于复合光催化剂比表面积增大，光生电子与空穴的分离加快。

关键词  锡酸铋Bi2Sn2O7(BSO) 氮化碳g-C3N4 复合材料 光催化

 

毕业设计说明书外文摘要

Title   The  fabrication  of  Bi2Sn2O7/g-C3N4  composite  material                   

        and  appliaction  in  photocatalysis                                

Abstract

Bi2Sn2O7(BSO) is a new semiconductor which has a promising applicaiton in photocatalysis due to its low-cost, non-toxicity and chemical-stability. However, the photocatalytic activity of single phase BSO is not satisfying . In this paper, for the first time, BSO/g-C3N4 composite photocatalysts were synthesized by high temperature solid-state recation method and different contents of g-C3N4 for the photocatalytic activity was studied. The obtained BSO/g-C3N4 was characterized by XRD, TEM, SEM, XPS and UV-vis. We eva luated the photocatalytic activity through the degradation of methylene blue as a target pollutant under visible light. The result showed the photocatalytic performance of the BSO/g-C3N4 composites under visible light irradiation was enhanced compared with pure BSO. In addition, the best crystal morphology and photocatalytic efficiency was achieved when the mass ratio of g-C3N4 was 60%. The excellent photocatalytic performance was attributed to the increased surface area and efficient separation of photogenerated electrons and holes result from the coupling of BSO and g-C3N4.

Keywords  Bismuth stannate Bi2Sn2O7(BSO)  Carbon nitride g-C3N4  Composite material   photocatalysis

 

目   次

1  绪论 1

1.2   BSO粉末材料的制备方法 2

1.2.1  水热合成法 2

1.2.2  高温固相法 3

1.2.3  溶胶凝胶法(胶体化学法) 3

1.3  提高半导体光催化效率的方法 4

1.3.1  离子掺杂 4

1.3.2  非金属元素掺杂 4

1.3.3  复合半导体 4

1.3.4  表面负载 5

1.4  本文研究内容及思路 5

1.5  表征方法和原理 6

1.5.1  X射线衍射(XRD) 6

1.5.2  扫描电子显微镜(SEM） 6

1.5.3  透射电子显微镜(TEM） 7

1.5.4  紫外可见漫反射光谱(UV-vis DRS） 7

1.5.5   X射线光电子能仪(XPS) 7

2  催化剂的制备 8

2.1  实验药品与仪器 8

2.1.1  实验药品 8

2.1.2实验仪器与设备 8

2.2  实验步骤 8

2.2.1  粉末的制备 8

2.2.2  催化剂性能测试 9

3  结果与讨论 10

3.1  物相及形貌分析 10

3.2  元素分析 12

3.3  紫外一可见吸收分析 13

3.4  光催化结果分析 14

4  光催化降解机理 16

结  论 17

致    谢 19

参 考 文 献 20