化单壁碳纳米管的热化学
H F Bettinger1, K N Kudin, G E Scuseria
1Department of Chemistry, MS-60, Center for Nanoscale Science and Technology, Rice University, P.O. Box 1892, Houston, Texas 77251-1892, USA.
Journal of the American Chemical Society
|December 26, 2001
概括
化碳纳米管具有更高的稳定性和更强的C-F键,直径更小. 在纳米管内,的共价结合是可能的,与富勒不同.
科学领域:
- 计算化学计算化学
- 材料科学 材料科学 材料科学
- 纳米技术纳米技术
背景情况:
- 碳纳米管 (CNT) 是具有独特电子和机械性能的多功能材料.
- 化CNT可以显著改变其性能,导致在各种领域的潜在应用.
- 了解化碳纳米结构的行为对于设计先进材料至关重要.
研究的目的:
- 为了研究化扶手椅单壁碳纳米管 (F-SWNTs) 和化石墨烯板的几何和能量.
- 为了确定管径对F-SWNTs热力学稳定性和C-F键强度的影响.
- 探索SWNT中原子的内体共价结合的可能性.
主要方法:
- 密度函数理论 (DFT) 的计算使用梯度校正的Perdew-Burke-Ernzerhof函数.
- 使用3-21G基础集和周期性边界条件来模拟纳米管和石墨烯.
- 使用异体方程来评估热力学稳定性.
主要成果:
- 随着管径的减少,F-SWNTs的热力学稳定性会增加.
- 平均C-F键解离能量随着管径的减少而增加.
- 较小的F-SWNT中的C-F键很强,与石墨化物相当,并且呈现轻微的拉伸.
- 在 (5,5) SWNT 内部可能发生共价结合,但在 C60 富勒烯的凸表面是不可能发生的.
结论:
- 直径较小的F-SWNT在热力学上更稳定,并且具有更强的C-F键.
- 在F-SWNT中,C-F键是共价的,它们的强度可以根据直径调节.
- SWNT提供了一个独特的环境,用于内分体共价函数的功能化,与烯子不同.
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