Abstract Chemical functionalisation of graphene and other 2-dimensional materials is a key step in realizing their full potential in various applications. There is a need for non-destructive and unambiguous identification of chemical groups and mapping of their distribution on such materials with nanoscale spatial resolution and at monolayer thicknesses. In this work, AFM-coupled infrared spectroscopy is used to analyse single layer reduced graphene oxide flakes that have been non-covalently functionalized with sulfonated pyrenes. We show this technique to be capable of distinguishing between the different pyrene moieties and mapping the sulfonate groups on a 1.7 nm functionalised monolayer of reduced graphene oxide with 32 nm spatial resolution. This technique is also shown to be sensitive to small changes in the sulfonate absorption spectra arising from chemical and surface effects, enough to distinguish between different functionalizing molecules even on materials with anisotropic thermal conductivity.

中文翻译：

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石墨烯上化学官能团的纳米级红外识别和映射

摘要 石墨烯和其他二维材料的化学功能化是在各种应用中充分发挥其潜力的关键一步。需要以纳米级空间分辨率和单层厚度对化学基团进行非破坏性和明确的鉴定，并绘制它们在此类材料上的分布图。在这项工作中，AFM 耦合红外光谱用于分析已用磺化芘非共价官能化的单层还原氧化石墨烯薄片。我们展示了这种技术能够区分不同的芘部分并将磺酸盐基团映射到 1.7 nm 功能化的还原氧化石墨烯单层上，空间分辨率为 32 nm。