Chair of Organic Chemistry II and Joint Institute of Advanced Materials and Processes (ZMP), Friedrich-Alexander University of Erlangen-Nuremberg, Henkestrasse 42, 91054 Erlangen, Germany.
Institut für Experimental Physik, Freie Universität Berlin, Arnimallee 14, 14195 Berlin, Germany.
Nat Commun. 2017 May 8;8:15192. doi: 10.1038/ncomms15192.
The verification of a successful covalent functionalization of graphene and related carbon allotropes can easily be carried out by Raman spectroscopy. Nevertheless, the unequivocal assignment and resolution of individual lattice modes associated with the covalent binding of addends was elusive up to now. Here we present an in situ Raman study of a controlled functionalization of potassium intercalated graphite, revealing several new bands appearing in the D-region of the spectrum. The evolution of these bands with increasing degree of functionalization from low to moderate levels provides a basis for the deconvolution of the different components towards quantifying the extent of functionalization. By complementary DFT calculations we were able to identify the vibrational changes in the close proximity of the addend bearing lattice carbon atoms and to assign them to specific Raman modes. The experimental in situ observation of the developing functionalization along with the reoxidation of the intercalated graphite represents an important step towards an improved understanding of the chemistry of graphene.
拉曼光谱可轻松验证石墨烯和相关碳同素异形体的共价功能化是否成功。然而，迄今为止，与添加物的共价键合相关的个别晶格模式的明确分配和分辨率仍难以实现。在这里，我们进行了一项原位拉曼研究，研究了钾插层石墨的受控功能化，揭示了光谱 D 区出现的几个新谱带。这些谱带随着功能化程度从低到中水平的增加而演变，为解卷积不同成分提供了基础，从而定量确定功能化程度。通过互补的 DFT 计算，我们能够识别出添加物承载晶格碳原子附近的振动变化，并将其分配给特定的拉曼模式。原位实验观察功能化的发展以及插层石墨的再氧化，是朝着更好地理解石墨烯化学迈出的重要一步。
