溶解在 mesophase:一个化学家的方法准备碳纳米和微粒的方法
Lileta Gherghel1, Christian Kübel, Günter Lieser
1Max Planck Institute for Polymer Research, Ackermannweg 10, 55128 Mainz, Germany.
Journal of the American Chemical Society
|October 31, 2002
概括
这项研究引入了一种新的火溶解方法,可以从六次-四次-赫克萨本佐可罗前体中制造出独特的碳纳米粒子. 该过程在高温下保持液晶秩序,使控制的碳材料合成成为可能.
科学领域:
- 材料科学 材料科学 材料科学
- 纳米技术纳米技术
- 有机化学 有机化学
背景情况:
- 碳纳米材料的合成对于先进的应用至关重要.
- 现有的方法通常需要恶劣的条件或产生有限的结构控制.
- 石墨化过程涉及从碳化合物前体中形成碳二相.
研究的目的:
- 开发一种用于产生新型碳微粒子和纳米粒子的温和火溶性方法.
- 研究液晶相在碳材料形成中的作用.
- 探索合成石墨碳结构的新途径.
主要方法:
- 热解六甲基替代的六甲--hexabenzocoronene.
- 使用前体的光盘液晶相.
- 使用矩阵辅助激光脱/离子化飞行时间 (MALDI-TOF) 质谱,光学显微镜,选区电子衍射 (SAED),扫描电子显微镜 (SEM) 和高分辨率传输电子显微镜 (HRTEM) 进行表征.
主要成果:
- 成功地产生了前所未有的碳微粒和纳米粒子.
- 证明在链裂变过程中,液晶秩序在400°C以上持续存在.
- 鉴定证实了石墨碳结构的形成.
结论:
- 拟议的轻度火溶性方法为新型碳纳米材料提供了一条受控的途径.
- 液晶秩序的持久性是合成过程的关键.
- 这种方法为传统的石墨化技术提供了替代方案.
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