【作者】 冷春波；

【导师】 卢士香；

【作者基本信息】 北京理工大学 ， 化学， 2010， 硕士

【摘要】 在纳米热席卷全球的高科技时代,纳米ZnO因其特有的表面效应、小尺寸效应等特性,广泛应用于橡胶、陶瓷、涂料等行业,并还可用于光催化剂、导电材料、磁性材料等。ZnO的禁带宽度为3.2 eV,对应于波长为387 nm的紫外光。作为一种重要的光催化材料,近年来得到了广泛的研究。但是纯氧化锌的光催化效率低,难以实现工业化应用。半导体材料复合或掺杂能够改善其光催化性能,因此引起了科学界的广泛关注。本文以乙酸锌（Zn（CH₃COO）₂·2H₂O）、氢氧化锂（LiOH·H₂O）、结晶氯化镉（CdCl₂·2.5H₂O）结晶氯化铝（AlCl₃·6H₂O）为原料,采用溶胶-凝胶法制备了纯纳米ZnO、掺杂镉离子的ZnO和镉铝共掺的ZnO,并用紫外灯作为光源,一定浓度的活性艳蓝X-BR为光催化反应模型污染物,研究了各种ZnO的光催化性能。比较了不同掺杂量镉和镉铝共掺对降解率的影响。采用X射线衍射（XRD）光谱、傅立叶红外（FT-IR）光谱、紫外-可见（UV-Vis）吸收光谱、X光电子能谱（XPS）和高分辨透射电子显微镜（HR-TEM）对其进行了表征。结果表明,各掺杂粒子均匀的掺入了ZnO晶格中,掺杂镉离子及镉铝共掺使纳米粒子的均匀度增加,且粒径明显变小,提高了ZnO的光催化活性。单掺样品中镉离子掺杂量为0.5%的ZnO的光催化性能最好。共掺样品中0.2%Cd²⁺-4.5%Al³⁺的ZnO的光催化性能最好,在30℃下,加入催化剂浓度为0.1 g/L,降解时间为60 min时,对浓度为20 mg/L的活性艳蓝X-BR溶液的降解率达到76.49%。更多还原

【Abstract】 Nanometer material is known as the 21 most promising materials", particularly nanometer ZnO possesses special properties such as superficial effect and volumetric effect. It is widely used in the industries of pottery, coating, rubber and so on and can also be used as the materials in the photocatalyst, conduction, magnetism etc. The energy gap of bulk material ZnO is 3.2 eV, corresponding to the ultraviolet light of the wavelength 387 nm. As a kind of important photocatalyst, semiconductor material-ZnO has been widely studied in recent years. It is difficult to be applied in engineering due to the lower photocatalytic efficiency of pure ZnO, which however can be improved by compounding semiconductors or doping, therefore it has become the subject of increasing attention in the scientific field.In this paper, pure ZnO , Cd²⁺-doped ZnO and Cd²⁺-Al³⁺ co-doped ZnO were prepared using sol–gel method with zinc acetate dehydrate [Zn（CH₃COO）₂·2H₂O], lithium hydroxide monohydrate （LiOH·H₂O）, cadmium chloride （CdCl₂·2.5H₂O）, aluminum chloride （AlCl₃·6H₂O） as raw material. The samples were characterized by means of X-ray diffraction （XRD）, infrared absorption spectroscopy （IR）, UV-Vis spectroscopy and high resolution transmission electron microscope（HR-TEM）. The photocatalytic performance of different ZnO samples were studied using ultraviolet lamp as illumination device and reactive brilliant blue X-BR as stimulant pollutant. The relationship between the amount of Al³⁺ doping or Cd²⁺-Al²⁺-codoping with degradation rate was also discussed.The results indicated that the doping was well-proportioned doped into ZnO sample.Moreover Cd²⁺ dopants or Al³⁺-Cd²⁺ co-doping in ZnO increased the uniformity of the particles and make the particle remarkably smaller so that they are efficient to improve the photocatalytic performance of ZnO. In particular, among the samples of single dopant, 0.5%Cd²⁺-doped particle ,has the best photocatalytic performance and sa dose 0.2%Cd²⁺-4.5%Al³⁺ co-doped ZnO particle in the co-doped samples. We also found a quantitative result that when the reaction temperature was 30℃, the degradation rate of reactive brilliant blue X-BR could reach 76.49% by catalyst of 0.1 g/L in 60 min.更多还原