Depth profiling at interfaces by combining phase-sensitive sum and difference frequency generation spectroscopies

Place: conference hall, IMDEA Nanociencia.

Abstract: 

Second-order surface-sensitive vibrational Sum and Difference Frequency Generation (SFG & DFG) spectroscopies are powerful tools for investigating aqueous interfacial dynamics, which are central to many natural and technological processes. Traditional SFG & DFG measurements, however, often suffer from interference by parasitic higher-order signals, limiting our ability to isolate true interfacial responses and fully exploit the wealth of information they contain. In this talk, I will introduce a novel, phase-resolved SFG and DFG approach designed to overcome these limitations, providing a remarkably clean dipolar interfacial signal with sub-nanometric depth resolution. This advancement opens new avenues for exploring key properties of aqueous interfaces, such as the interfacial ‘healing depth’ of water. This cutting-edge technique, soon to be implemented at IMDEA Nanoscience, promises to reveal unprecedented insights into the interfacial behavior of water under various conditions, including in situ during photocatalytic and electrocatalytic reactions, as well as in the presence of biologically relevant molecules.