酵母菌模板法制备氧化物空心微纳米材料的研究

发布时间：2018-07-08 21:10

  本文选题：生物模板 + 空心微球　； 参考：《山东科技大学》2017年硕士论文

【摘要】：空心结构的微纳米金属氧化物由于密度低、比表面积大等特点,使其具有许多块体材料所不具备的性能,并因其在环境保护、能量存储、生物医药等领域的应用而引起了研究者的广泛关注。目前,制备空心结构微纳米金属氧化物的方法主要为模板法,在众多的可用模板中,使用天然生物质作模板由于模板形貌多样,数量巨大,对环境无污染,且省去了模板制备的过程,产物制备条件温和而成为制备金属氧化物空心结构的一个极具潜力的研究方向。本论文采用简单易得的单细胞真菌酵母菌为模板,辅助沉淀法,之后经高温锻烧制得了微纳米氧化铈空心球体,并考察了硫酸高铈浓度、陈化时间、煅烧温度、表面活性剂等对产物形貌的影响。通过X射线衍射(XRD)、傅里叶转换红外光谱(FT-IR)、X射线光电子能谱(XPS)、扫描电子显微镜(SEM)、透射电子显微镜(TEM)等方法对产物的形貌结构进行了表征,对其形成机理进行了解释,并对其光学性能进行了测试。实验结果表明,当硫酸高铈浓度为0.5 moI·L-1,氢氧化钠浓度为1 mol·L-1时,不添加任何表面活性剂,陈化时间为12 h,锻烧温度为600℃的条件下可以得到分散良好、形貌规则的CeO2空心微球。其粒径在2.0μm～3.0μm之间,形貌与酵母菌模板一致为椭球体,呈现立方晶型结构。将所得的CeO2空心微球用作光催化剂,研究了其光催化降解染料废水的性能。空心氧化铈的比表面积为21.85 m2·g-1,比无模板氧化铈的比表面积(5.37 m2·g-1)明显增大,禁带宽度为3.03 eV,比无模板氧化铈禁带宽度(3.42 eV)明显减小。光催化实验结果表明,制得的微纳米氧化铈空心球在太阳光照射下可有效催化降解溶液中的酸性橙(AO 7),在照射120 min之后降解率能达到96%以上,降解效果明显高于未使用模板的氧化铈微粒。此外,同样以酵母菌为模板,硝酸铟为铟源,制备得到纯度较高的氧化铟空心微纳米球。通过表征分析,所制备的氧化铟空心球同样保持了模板的形貌,比表面积为19.23 m2·g-1,禁带宽度为3.28 eV,在太阳光照射180 min后,对亚甲基蓝的降解率可达91.91%,具有较强的光催化性能。
[Abstract]:Because of its low density and large specific surface area, hollow metal oxides have many properties that many bulk materials do not have, and because of their environmental protection, energy storage, The application of biomedicine and other fields has attracted wide attention of researchers. At present, the main preparation method of hollow structure micro-nano metal oxide is template method. In many available templates, natural biomass is used as template because of the diversity of template morphology, large number of templates, no pollution to the environment. The preparation conditions of the products are mild, which makes them a potential research direction for the preparation of metal oxide hollow structures. In this paper, micronanocrystalline cerium oxide hollow spheres were prepared by using simple and easily obtained single cell fungal yeast as template, assisted precipitation method, and then calcined at high temperature. The concentration of cerium sulfate, aging time and calcination temperature were investigated. The influence of surfactants on the morphology of the products. The morphology and structure of the products were characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM) and transmission electron microscope (TEM). The optical properties were tested. The experimental results show that when the concentration of cerium sulfate is 0.5 mol / L, the concentration of sodium hydroxide is 1 mol / L, no surfactant is added, the aging time is 12 h, and the calcination temperature is 600 鈩，

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