The conductivity of few‐ and monolayer graphene with covalently bound moieties is a key‐point in the potential application of these materials in any electrical and optoelectronic device. In particular, fluorination of such graphene‐based systems is of interest, as fluorine is expected to have a strong influence on the charge‐carrier density due to its high electronegativity, and therefore modify the electrical transport properties significantly. Here it is shown that, depending on the device architecture, the electrical properties of fluorinated graphene‐based devices are significantly different. It is found that the conductivity of thin films of few‐layer graphene decreases by several orders of magnitude with fluorine content increasing from 2.4 to 16.6 at%, whereas individual flakes show a significant increase in both conductivity and charge carrier mobility. This observation, combined with Raman microscopy study, points toward the fact that the edges of the flakes are primary sites for fluorine within the experimental range of fluorine content. The strong decrease in conductivity in the film devices is therefore associated with the high contact resistance between the fluorine saturated edges of the individual flakes.

中文翻译：

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基于边缘氟化石墨烯的器件中的电传输

具有共价键合部分的单层和单层石墨烯的电导率是这些材料在任何电气和光电设备中潜在应用的关键点。尤其值得关注的是这种基于石墨烯的体系的氟化，因为人们期望氟由于其高电负性而对电荷载流子密度产生强烈影响，因此会显着改变电传输性能。此处显示出，根据设备架构的不同，基于氟化石墨烯的设备的电性能存在显着差异。结果发现，随着氟含量从2.4at％增加到16.6at％，几层石墨烯薄膜的电导率降低了几个数量级，而单个薄片则显示出电导率和载流子迁移率的显着提高。该观察结果与拉曼显微镜研究相结合，指出了以下事实：薄片的边缘是在氟含量的实验范围内的主要氟原子位点。因此，薄膜器件中电导率的强烈下降与各个薄片的氟饱和边缘之间的高接触电阻有关。