基于核磁共振的石墨氧化物的结构建模使用多维13C固态核磁共振和初始化学转移计算
Leah B Casabianca1, Medhat A Shaibat, Weiwei W Cai
1Department of Chemistry, University of Illinois at Chicago, 845 West Taylor Street, Chicago, Illinois 60607, USA.
Journal of the American Chemical Society
|April 3, 2010
概括
本研究介绍了一种固态核磁共振 (SSNMR) 方法来建模石墨氧化物结构. 这些发现证实了Lerf-Klinowski模型,揭示了在改性石墨烯材料中相互连接的sp{2),1,2-环氧化物和COH碳.
科学领域:
- 材料科学 材料科学 材料科学
- 纳米技术纳米技术
- 化学 化学 化学
背景情况:
- 化学修饰的石墨烯和石墨材料对电子和结构应用很感兴趣.
- 使用光谱数据对基于非晶体石墨的材料进行精确的结构建模具有挑战性.
研究的目的:
- 开发和介绍一种基于固态NMR (SSNMR) 的方法,用于构建氧化石墨 (GO) 的结构模型.
- 为了验证GO的结构模型,一个关键的改性石墨烯前体.
主要方法:
- 使用2D (13)C双量子/单量子相关性SSNMR光谱在标记13C的GO上.
- 对比各种结构模型的实验光谱与基于初始几何优化和化学转移计算的模拟.
- 采用2D (13)C化学转移异型 (CSA) /异型转移相关性SSNMR来分析CSA模式.
主要成果:
- GO的实验SSNMR光谱最好通过基于Lerf-Klinowski模型的几何优化模型重现.
- 这种经过验证的模型包括相互连接的sp(2),1,2-环氧化物和COH碳.
- 之前提出的模型,包括那些含有1,3-环氧化碳的模型,被排除在外.
- 计算的化学转移张量器准确地重现了测量的 (13) C CSA 模式.
结论:
- 基于SSNMR的方法有效地模拟了氧化石墨的结构.
- 莱尔夫-克利诺夫斯基模型,其特定的碳排放安排,被强烈支持.
- 这种方法适用于对其他改性石墨烯和基于石墨的系统进行结构分析.
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