Tip-Enhanced Raman Scattering with a Nanoparticle-Functionalized Probe

摘要

We carried out the tip-enhanced Raman scattering (TERS) with a tip that is functionalized with a Au-nanoparticle (AuNP, with a diameter of 250 run). The AuNP tip is fabricated by a direct mechanical pickup of a AuNP from a flat substrate, and the TERS signal from the AuNP tip - organic monolayer - Au thin film (thickness of 10 nm) is recorded. We find that such a AuNP-tip interacting with a thin film routinely yields signal enhancement larger than ~104, which is sufficient not only for local (with detection area of ~200 nm~2) Raman spectroscopy, but also the nanometric imaging of organic monolayers within a reasonable acquisition time (~20 minutes/image).