Tip enhanced Terahertz - Raman for investigating graphene-water interactions at the nanoscale

本项目研究了通过化学气相沉积在Au（111）表面生长石墨烯的方法。采用STM、STS和STM- ters对样品进行调查。STM成像显示了石墨烯中典型的蜂窝结构和云纹图案。STM-TERS光谱显示石墨烯的G、D和2D带。此外，光谱显示了g波段的分裂，我们将其归因于单轴应变和石墨烯层上缺陷的存在。除了单点STM-TERS测量外，我们还能够进行STM-TERS映射。由于拉曼信号较弱，STM-TERS映射具有挑战性，因为它需要较长的采集时间。为此，我们利用了自己设计的自动化远程实验系统。这使得我们可以在不实际出现在实验室内的情况下方便安全地进行实验。映射的结果揭示了在STM图像中没有观察到的域边界的存在。

For this project, graphene grown on Au(111) surface via chemical vapour deposition was investigated. Samples were investigated using STM, STS and STM-TERS. STM imaging revealed the honeycomb structure and Moire patterns typically observed in graphene. The STM-TERS spectra showed the G, D and 2D band of graphene. Moreover, the spectra showed a splitting of the G-band which we attribute to a combination of uniaxial strain, and the presence of defects on the graphene layer. Apart from single point STM-TERS measurement, we were also able to perform STM-TERS mapping. Because of weak Raman signals, STM-TERS mapping is challenging as it required long acquisition times. For this, we utilized the automated remote experiment system we designed. This allowed us to conveniently and safely perform the experiment while not being physically present in the experimental room. The results of the mapping revealed the presence of a domain boundary which was not observed in the STM images.