Self-assembly structure of CeO2 nanoparticles: synthesis, characterization and catalytic property
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摘要: 利用微乳液方法(以AOT为表面活性剂)自组装合成了叶脉状结构的CeO2(氧化铈)纳米粒子;使用X射线衍射仪(XRD)、透射电子显微镜(TEM)、括展X射线精细结构(EXAFS)对其进行了研究表征;并对其催化特性进行了测试. XRD结果表明CeO2纳米粒子为立方面心结构;EXAFS结果表明与体相CeO2微粒相比,Ce－O键长变长,Ce原子周围O原子配位数降低;催化特性研究结果表明,相对于体相材料,CeO2纳米微粒的催化分解H2O2的活性大大提高.Abstract: A new approach to synthesis of self-assembly CeO2 nanoparticles by using microemulsion method was investigated. The structure of the product was characterized by the methods of X-ray diffraction (XRD), transmission electron microscopy (TEM), and extended X-ray absorption fine structure (EXAFS). XRD result indicates the face-center cubic(FCC) structure of the produced CeO2 nanoparticles. EXAFS shows that the oxygen coordination number around Ce in CeO2 nanoparticles decrease compared with the bulk CeO2, and the bond-length of Ce-O in CeO2 nanoparticles is obviously longer than that of bulk materials. The catalytic property of CeO2 on the decomposition of H2O2 was investdigated, and the results demonstrate that CeO2 nanoparticles have much stronger catalytic activity than bulk CeO2.
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Key words:
- cerium oxide /
- synthesis /
- microemulsion /
- self-assembly structure
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