半孔式Co3O4和Au/Co3O4催化剂用于微量乙烯的低温氧化
Chun Yan Ma1, Zhen Mu, Jin Jun Li
1State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, PR China.
Journal of the American Chemical Society
|February 10, 2010
概括
高活性氧化物 (Co3O4) 催化剂,包括金色装饰的变种,在0°C时有效氧化微量乙烯. 的{110}晶体面是这种增强的催化性能的关键.
科学领域:
- 材料科学 材料科学 材料科学
- 催化剂是一种催化剂.
- 纳米技术 纳米技术
背景情况:
- 开发高效的低温催化剂对于环境应用至关重要.
- 氧化物 (Co3O4) 是一个有前途的催化材料,但它的性能高度依赖于结构和暴露的方面.
- 在低温下乙烯氧化是由于低反应动力学而面临的重大挑战.
研究的目的:
- 为了合成和表征中等孔C03) O04) 和Au/C03) O04) 催化剂.
- 调查晶体面在乙烯氧化催化活性中的作用.
- 为了在接近环境温度 (0°C) 的微量乙烯氧化中获得高的催化性能.
主要方法:
- 纳米造方法使用KIT-6的模板来制造半孔性Co(3) O(4).
- 通过将金纳米颗粒纳入Co{3}O{4}介孔结构来合成Au/Co{3}O{4}.
- 高分辨率传输电子显微镜 (HRTEM) 用于结构和形态分析.
- 在0°C时对微量乙烯氧化的催化试验.
主要成果:
- 与Co(3) O(4) 纳米薄膜相比,中孔 Co(3) O(4) 对乙烯氧化具有显著更高的活性.
- 鉴定出中孔C03) O04) 的 {110} 面是活性表面,对催化性能至关重要.
- Au/Co(3) O(4) 催化剂在0°C实现了创纪录的76%的乙烯转化,归因于稳定,分散的金纳米粒子和增强的表面活性氧物种.
结论:
- 在其催化氧化性能中,Co(3) O(4) 的{110}晶面在催化氧化性能中起着关键作用.
- 半孔C03) O04) 和Au/C03) O04) 是高效的低温催化剂,用于乙烯氧化.
- 开发的催化剂为在低温下有效去除微量乙烯提供了有希望的解决方案.
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