在单壁碳纳米管束中高温转换的实验热力学
Daniele Gozzi1, Alessandro Latini, Laura Lazzarini
1Dipartimento di Chimica, SAPIENZA Università di Roma, Piazzale Aldo Moro 5, 00185 Roma, Italy. daniele.gozzi@uniroma1.it
Journal of the American Chemical Society
|August 7, 2009
概括
测量了转化为石墨的单壁碳纳米管 (SWCNTs) 的热力学特性. 在高压下捆绑结构的变化会影响这些热力学量.
科学领域:
- 材料科学 材料科学 材料科学
- 热力学是一种热力学.
- 纳米技术纳米技术
背景情况:
- 单壁碳纳米管 (SWCNTs) 是一种具有独特性质的显著碳异形体.
- 了解SWCNTs转化为石墨对于材料科学应用至关重要.
- 在不同条件下的SWCNT的热力学行为需要详细的研究.
研究的目的:
- 为了确定与SWCNT捆中的碳转化为石墨中的碳相关的热力学量.
- 为了研究这种转换的温度依赖性和可逆性.
- 为了将SWCNT捆中的结构变化与热力学数据相关联.
主要方法:
- 使用CaF2固体电解质电池进行750到1015K之间的测量.
- 使用低角度X射线衍射 (XRD),微拉曼光谱和高分辨率传输电子显微镜 (HR-TEM) 进行结构分析.
- 分析了细胞的电机力,以计算标准和变化.
主要成果:
- 电电池的电机力表现出强烈的温度依赖性和可逆性.
- 标准和变化在不同的温度 (778,883和975K) 得到量化.
- 结构分析证实,由于内部压力,捆绑变形和形成稳定,相互转换的捆绑状态.
结论:
- SWCNTs转化为石墨受到SWCNT捆内温度依赖的结构重排的影响.
- 由热膨胀约束产生的高内部压力导致管形状和格子的显著变形.
- 这项研究提供了宝贵的热力学数据和对SWCNT捆的结构稳定性的见解.
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