氧气诱导的双壁碳纳米管边缘上的唇唇相互作用
Yong Soo Choi1, Kyung Ah Park, Changwook Kim
1Department of Physics, Institute of Basic Science, Center for Nanotubes and Nanostructured Composites, Sungkyunkwan University, Suwon 440-746, Korea.
Journal of the American Chemical Society
|July 30, 2004
概括
双壁碳纳米管 (DWCNTs) 上的氧分子吸附是外热的,并且在能量方面有利. 这个过程解释了DWCNT的化学稳定性,并影响了扶手椅纳米管中的场辐射.
科学领域:
- 材料科学 材料科学 材料科学
- 物理化学 物理化学
- 纳米技术纳米技术
背景情况:
- 双壁碳纳米管 (DWCNTs) 具有独特的化学和电子特性.
- 了解分子-纳米管相互作用对于催化和电子学的应用至关重要.
- 在各种条件下,DWCNTs的化学稳定性需要进一步研究.
研究的目的:
- 为了研究在DWCNT边缘上氧分子 (O(2) 的吸附.
- 阐明O(2) 吸附的机制及其对DWCNT结构和稳定性的影响.
- 探索吸附在DWCNTs的野外发射特性中的作用.
主要方法:
- 使用密度函数理论 (DFT) 的计算.
- 模拟的重点是在开放的DWCNT边缘上对O2的吸附.
- 分析包括吸附能量,反应途径和电子状态.
主要成果:
- ) 在DWCNT边缘的吸附是外热的,具有显著的吸附能量 (~ -9 eV).
- 分离性吸附导致自发的唇唇相互作用,关闭管末.
- 场辐射主要通过桥接碳原子的局部状态发生,而不是吸附氧气.
结论:
- DWCNT边缘很容易吸附O2分子,形成稳定,封闭的结构.
- 与单壁纳米管相比,这种吸附机制有助于提高DWCNTs的化学稳定性.
- 这些发现提供了对DWCNTs的化学行为和现场排放机制的见解.
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