Nanoscale characterization of graphene and polymer blends using tip-enhanced Raman spectroscopy and 3D surface-enhanced Raman spectroscopy

摘要

My thesis consists of two parts. The first part is concerned with tip-enhanced Raman scattering (TERS) of graphene. TERS is a technique which utilizes the enhanced electric field from the plasmon resonance between excitation laser and metallic nanotips to provide Raman signal from a small area around the tip exped. The nanoscale size of tip-apex allows spatial resolution TERS to exceed the diffraction limit of light, and thus capable of nanosensing. In this thesis, TERS was employed to explore nanos-tructures on epitaxial graphene. The downshift of G' band on nanoridge compared to nearby areas supports the hypothesis that graphene nanoridges form as a relief against compressive strain (Figure 1) (J. Phys. Chem. C 118,44, 25809-25815). TERS have also been used to characterize epitaxial graphene microisland, which enables the discussion between possibles mechanism of nanoridges formation (Phys. Chem. Chem. Phys. 17,43, 28993-28999).