富勒单壁碳纳米管异质连接的电荷转移结构-反应性依赖性
Andrew J Hilmer1, Kevin Tvrdy, Jingqing Zhang
1Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA.
Journal of the American Chemical Society
|July 16, 2013
概括
单壁碳纳米管 (SWCNT) 和富勒伦之间的电荷转移是光电子学的关键. 与较小的富勒烯衍生物不同,C85甲富勒烯显示了SWCNTs的增强电子转移和火效率.
科学领域:
- 材料科学 材料科学 材料科学
- 纳米技术 纳米技术
- 物理化学 物理化学
背景情况:
- 单壁碳纳米管 (SWCNT) - 富勒烯接口的电荷转移对于光伏和光电子设备至关重要.
- 在溶液中单个实体水平上分散烯和SWCNT是具有挑战性的,但对于详细研究是必要的.
- 了解结构-反应性关系对于优化这些混合材料至关重要.
研究的目的:
- 合成和研究特定度的SWCNT和各种甲富勒烯两性体之间的电子转移.
- 为富勒-SWCNT异构连接建立结构-活性关系.
- 评估不同富勒烯衍生物在基于SWCNT的光电子应用中的潜力.
主要方法:
- 合成甲富勒烯两性化物,包括C60,C70和C84的衍生物.
- 在水溶液中对功能化SWCNT和合成的富勒两性蛋白之间电子转移的光谱检测.
- 马库斯理论的应用,以建模和预测电子转移动态.
主要成果:
- 脂质-C61-聚乙烯甘醇 (PEG) 和脂质-C71-PEG在所有SWCNT物种中显示不完全火,这表明电子转移的驱动力很小.
- 马库斯理论支持了这些发现,预测能量偏移比SWCNT中的激子结合能量小.
- 将SWCNT与C85甲富勒烯接口导致所有半导体SWCNT的完全火,这归因于更深的LUMO水平.
结论:
- 电子转移效率严重依赖于烯衍生物的分子量和LUMO水平.
- 与较小的富勒烯 adducts 相比,C85甲富勒烯在灭半导体SWCNT方面表现优越.
- 这些发现凸显了C85甲富勒烯在光电学中开发先进的SWCNT-富勒烯异质连接的前景.
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