摘要:通过一个沉积沉淀路线,合成多种不同浓度的ZnO/ZnFe2O4和相同浓度ZnO/MFe2O4的核壳结构半导体材料。随后对ZnO,ZnO/ZnFe2O4和ZnO/MFe2O4核壳结构半导体材料进行了表征,分别是X射线衍射,N 2物理吸附测量,紫外可见光吸收光谱和二氧化碳吸附的FTIR。表征结果证实,所得ZnO/MFe2O4复合材料具有高比表面积,能减小光的吸附能力,并且不会影响晶体结构的优点。通过反应性能和CO2-FTIR发现,引入适当的二价金属阳离子可以有效地促进CO2吸附和增强生成的b-CO32-中间体,增加二价阳离子改性相的ZnO催化剂的甲烷与甲醇产量较纯的ZnO催化剂大大增加。本文通过结合光催化还原的活性和特点,提出了关于半导体催化剂上利用其表面性质(面点/组,反应中间体)进行二氧化碳的光还原,启发了一个目前很少人研究但是却很有前景的研究信息。61852
毕业论文关键词:二价阳离子改性氧化锌;二氧化碳光催化;二氧化碳吸附中间体;面点
Preparation of MFe2O4-ZnO semiconductor materials and the effect of cations on photocatalytic reduction of CO2
ABSTRACT: The core shell structure semiconductor materials with different concentrations of ZnO/ZnFe2O4 and the same concentration of ZnO/MFe2O4 were synthesized by a deposition precipitation route. Subsequently, ZnO, ZnO/ZnFe2O4 and ZnO/MFe2O4 core shell structures were characterized by X - ray diffraction, N 2 physical adsorption measurements, UV Vis absorption spectroscopy and carbon dioxide adsorption of FTIR. Characterization results show that the high specific surface area with income ZnO/MFe2O4 composite, can reduce the adsorption capacity of Hikari, and will not affect the crystal structure of the advantages. The reaction performance and CO2-FTIR found introducing appropriate palent metal cations can effectively promote adsorption of CO2 and enhanced generation of b-CO32- intermediates and increased palent cationic modification of ZnO catalyst of methane and methanol yield as compared to pure ZnO catalyst is greatly increased.In this paper, through a combination of photocatalytic reduction activity and characteristics, it puts forward a semiconductor catalyst on the surface properties (pasta / group, reaction intermediates) of light carbon dioxide reduction, inspired a at present a few people study but very promising research information.
KEYWORDS: Two valence cation modified ZnO;CO2phototreduction;CO2 adsorbed intermediate; surface sites
目 录
1.1研究的意义 1
1.2研究现状 2
1.2.1半导体材料在光催化还原CO2中的应用 2
1.2.2 ZnO材料在催化材料中的应用 3
1.2.3半导体光催化反应影响因素 4
1.2.4提高半导体光催化效率的方法 5
1.2.5半导体光催化剂的改性 6
2实验部分 9
2.1药品试剂及实验设备 9
2.1.1试剂 9
2.1.2实验器材 9
2.2半导体材料的制备 10
2.2.1 ZnO纳米棒制备 10
2.2.2 ZnO-ZnFe2O4制备 10
2.2.3 ZnO-MFe2O4制备 10
2.3半导体催化剂的表征 10
2.4 半导体催化剂光催化还原CO2性能的评价 11