With the support of the Analytical and Surface Chemistry Program, Professor Richard Van Duyne of Northwestern University is investigating the optical properties of individual metal nanoparticles. Strategies are being developed for tailoring particles with optimized characteristics for use in ultra-sensitive chemical sensing platforms. Optical microscope techniques with integrated probe microscopy are applied to perform localized surface plasmon resonance (LSPR) scattering spectroscopy experiments on individual particles. Particles with controlled and well-defined size, shape and composition are prepared by casting materials inside nanowell templates through reactive ion etching and electron beam deposition. Strategies are also being pursued for the study of single molecule properties through surface enhanced Raman scattering and tip-enhanced Raman spectroscopy (TERS) measurements.
The synthetic and detection strategies are improving sensitivity in chemical sensing and enabling new insights into localized chemical reaction sites with potential for application in catalysis and cell biology.