Chemistry Weekly Seminar - Erick Soares Lins, PhD Candidate
Erick Soares Lins, PhD candidate in the Department of Chemistry, University of Saskatchewan will present a seminar at 1:30 p.m. via Zoom.
Title
Time-resolved spectroelectrochemistry with Dual Optical Frequency Combs
Abstract
Combining spectroscopy with electroanalytical methods is an approach that greatly adds to the study of surface processes, one of the pillars of electrochemistry in its various applications – from energy generation to diagnostic sensing. Although great improvements have been achieved in the field by obtaining molecular information in such processes, the understanding in the time domain is limited by some experimental barriers inherent to current instrumentation. In the last decade, however, the advent of mid-Infrared emitting Quantum Cascade Lasers, allied to the technique of signal heterodyning led to the development of Dual Frequency Comb Spectroscopy (DFCS). It is a complete shift in paradigm that allows a time-resolution otherwise only achievable by extremely large collection of data in repeated spectral acquisitions. DFCS may reach in minutes the signal-to-noise quality that other methods would take days worth of measurements to get.
In this talk, I will describe what is the first application of time-resolved DFCS in an electrochemical context, as the commissioning of a novel instrument at the Canadian Light Source. Background and instrument operational principles will be outlined, discussing the advantages that it offers over the currently established Michelson interferometer for FTIR. I will also discuss Attenuated Total Internal Reflectance Surface-Enhanced Infrared Absorption Spectroscopy (ATR-SEIRAS) as an efficient tool to investigate electrical charge driven surface processes. I will describe the challenges faced in adapting the apparatus normally used with globar sources to that of a broadband laser source. Finally, the opportunity in obtaining kinetic information with less experimental limitations is addressed, as well as one direction to reduce electric potential rise time in the cell.
Date: Friday, April 9, 2021
Time: 1:30 p.m.
Via Zoom video conference (link available by request to chem.dept@usask.ca)