Seminar of Pr François Lagugné-Labarthet

François Lagugné-Labarthet is Professor at the Chemistry Department of the Western University (London, Canada). He is the scientific director of the Nanofabrication Facility at Western, a open-user facility that aims at training the next generation of nanoscale scientists.

Abstract

The past two decades have been very active in the development of tip-enhanced spectroscopy and of its application to a variety of materials and biomaterials with intricate properties at a nanoscale level. We present here our journey in this dynamic field applied to the study of nanomaterials and what knowledge it has brought to the field, its promises, its limitation and its challenges. In particular, we will focus on our most recent work applied to the study of 2D materials and how combination of Tip-enhanced Raman spectroscopy (TERS) and atomic force microscope (AFM) modes can be utilized jointly to decipher the optical and mechanical properties of 2D flakes of transition metal dichalcogenides with thickness of less than 1 nm. The presence of surface defects, growth of additional layers and surface functionalization are examples of nm features that can be revealed optically and mechanically from the combination of an Atomic Force Microscope and a confocal microscope. Current developments in machine-learning methods are also interesting tools that can be applied to analyse thousands of spectra collected a typical confocal or TERS mapping. We will present few examples on how such methods can be applied to Raman spectroscopy measurements and how it can help to decipher complex vibrational spectra.