Pairing Synchrotron Radiation with an ATR-Integrated Microreactor for In-Situ Spatiotemporal Characterization of Chemical Reactions
Date
2024-01-17
Authors
Journal Title
Journal ISSN
Volume Title
Publisher
ORCID
Type
Thesis
Degree Level
Masters
Abstract
Microfluidic devices consist of microfabricated structures designed to control minuscule
volumes of fluid with exceptional precision. The growth of this field has allowed researchers
to miniaturize lab-based processes, providing an alternative experimental approach
which is more efficient, safer, eco-friendly, and cost-effective. In-situ monitoring
of chemical reactions is greatly important to the field of chemistry. Real-time characterization
allows for a better understanding of the system by investigating the underlying
mechanisms and reaction kinetics. Fourier-transformed infrared (FTIR) spectroscopy is a
suitable technique to be coupled with microfluidics as it is non-invasive, straightforward,
reliable, and sensitive to molecular changes which occur during a reaction. With the use of
attenuated total reflection (ATR) FTIR spectroscopy, significant attenuation of radiation
by the fluidic environment is overcome. The quantitative capabilities of IR spectroscopy
coupled with a microfluidic device provide researchers with the ability to monitor reaction
variables such as reagent concentrations in-situ.
In this thesis, I evaluate the abilities of a unique microfluidic device equipped with
a single-bounce ATR element by monitoring a proof-of-concept chemical reaction using
synchrotron sourced IR radiation. The unique capabilities of the Mid-IR beamlines’ horizontal
ATR (hATR) endstation at the Canadian Light Source (CLS) allow the beam spot
to be positioned at any point along the length of the channel to assess the chemical environment
at many different reaction times. Coupling the endstation capabilities with the
single-bounce ATR accessory and synchrotron radiation allows different sensing areas to
be individually addressed, thereby providing the ability to obtain spatially and temporally
resolved information. This microreactor provided in-situ characterization, which was used
to spatially and temporally track the concentration changes throughout an SN2 reaction.
The collected measurements were then used to determine the kinetic rate constant of the
monitored reaction. Therefore, this thesis successfully demonstrates the microreactors’
impressive capabilities to monitor a reaction and extract kinetic parameters.
Description
Keywords
Synchrotron, microreactor, ATR, In-Situ, Spatiotemporal
Citation
Degree
Master of Science (M.Sc.)
Department
Chemistry
Program
Chemistry