单壁碳纳米管网络的电子特性
Elena Bekyarova1, Mikhail E Itkis, Nelson Cabrera
1Center for Nanoscale Science and Engineering, University of California, Riverside, California 92521, USA.
Journal of the American Chemical Society
|April 21, 2005
概括
单壁碳纳米管 (SWNT) 的化学功能化显著改变了它们的电子特性. 修改SWNT会影响导电能力,这对于开发基于SWNT的先进传感器至关重要.
科学领域:
- 材料科学 材料科学 材料科学
- 纳米技术纳米技术
- 凝聚物质物理学 凝聚物质物理学
背景情况:
- 单壁碳纳米管 (SWNTs) 具有独特的电子特性.
- 了解SWNT行为是传感器应用的关键.
- 薄膜导电性受到纳米管纯度和加工的影响.
研究的目的:
- 为了研究SWNT膜的电子特性.
- 为了证明化学功能化对SWNT导电性的影响.
- 阐明基于SWNT的传感器的机制.
主要方法:
- 使用喷雾沉积制备SWNT薄膜.
- 通过光学光谱学测量有效薄膜厚度.
- 在室温下电导率的表征及其温度依赖性.
主要成果:
- 准备和净化后的SWNT薄膜显示电导率为250-400S/cm.
- 非金属的温度依赖表明道障碍物主导导率.
- 使用ODA和PABS的化学功能化将导电率大幅降低到分别为3S/cm和0.3S/cm.
结论:
- 化学功能化极大地改变了SWNT的电子特性.
- 道障碍物对SWNT膜的导电性有很大的影响.
- 功能化效应为SWNT传感器机制提供了洞察力.
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