来自超声波喷雾热解的磁性和多孔纳米圈
Won Hyuk Suh1, Kenneth S Suslick
1School of Chemical Sciences, University of Illinois at Urbana-Champaign, 600 South Mathews Avenue, Urbana, Illinois 61801, USA.
Journal of the American Chemical Society
|August 25, 2005
概括
研究人员使用家用加湿器的超声波喷雾烧解来制造多孔的二氧化纳米颗粒. 这种方法允许控制孔径和高效封装纳米颗粒,产生耐氧化纳米球.
科学领域:
- 材料科学 材料科学 材料科学
- 纳米技术纳米技术
- 化学工程是化学工程的重要组成部分.
背景情况:
- 开发用于合成纳米材料的具有成本效益的方法对于先进的应用至关重要.
- 超声波喷雾热解提供了一个用于纳米粒子制造的多功能平台.
- 控制二氧化纳米颗粒的多孔性和表面性质是它们功能化的关键.
研究的目的:
- 开发一种廉价的超声波喷雾热解法,用于生产多孔的二氧化纳米粒子.
- 为了研究-有机复合材料的现场形成和随后的热解.
- 为了证明铁磁性纳米颗粒在多孔的二氧化中封装.
主要方法:
- 利用家用加湿器的廉价高频超声波发电机进行超声波喷雾热解.
- 采用两热区系统进行现场聚合和随后的聚合物热解.
- 改变了二氧化与有机单体的比率,以控制粒子形态和表面积.
- 通过使用SEM,TEM,EDS,XPS和SQUID来描述由此产生的多孔和封装的纳米圈.
主要成果:
- 成功生产了具有纳米尺度孔隙性的亚微米级二氧化颗粒.
- 通过调整二氧化与有机单体的比率来证明对二氧化粒子形态和表面积的控制.
- 在单一流程过程中,在多孔的二氧化矩阵内实现了铁磁性纳米颗粒的高效封装.
- 由此产生的-纳米圈对空气氧化具有很高的抗性.
结论:
- 建立了一种经济有效的超声波喷雾热解技术,用于制造可调节的多孔纳米颗粒.
- 开发的方法使磁纳米颗粒能够轻松地纳入保护性基质中.
- 产生的耐氧化-二氧化纳米圈有可能用于催化,传感和磁性存储的各种应用.
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