Applicability of standard kinetic parameters for describing a photothermally driven reaction
Open Access
- Author:
- Widstrom, Andrea Lyn
- Graduate Program:
- Chemistry
- Degree:
- Doctor of Philosophy
- Document Type:
- Dissertation
- Date of Defense:
- August 07, 2019
- Committee Members:
- Benjamin James Lear, Dissertation Advisor/Co-Advisor
Benjamin James Lear, Committee Chair/Co-Chair
Raymond Edward Schaak, Committee Member
John B Asbury, Committee Member
William D Burgos, Outside Member
Philip C Bevilacqua, Program Head/Chair - Keywords:
- Diels-Alder
photothermal
gold nanoparticle
solvent
kinetic
viscosity
retro Diels-Alder
dipole
activation
thermodynamic
Arrhenius - Abstract:
- Gold nanoparticles have been used to deliver nanoscale heat to drive chemical reactions using the photothermal effect. These applications range from polymerization to in vivo cancer therapy. While these sorts of transformations are well understood for bulk heating, an understanding of them is not well developed for photothermal heating. It is uncertain whether the standard theories for describing chemical reactivity, such as Arrhenius theory and transition state theory, will still hold under the extreme temperatures created by the photothermal effect. Photothermal heating is a very effective tool in chemistry, but in order for it to be useful it needs to be controllable. In order to control it, the response of chemical reactions to photothermal heating needs to be understood. Understanding the chemical behavior and properties that control or influence the generation of nanoscale heat is vital for future applications. Here, a set of retro Diels-Alder adducts are characterized using conventional heating to develop a baseline for comparison. These reaction are then used to determine how the rate of reaction is changed by photothermal heating. The photothermally driven rate enhancements are examined through the lens of solvent, in order to determine the influence of solvent properties on the reaction rate enhancement. This work demonstrates the importance of the dipole moment and viscosity of the solvent on the rate enhancement of the retro Diels-Alder reaction as driven by the photothermal effect. The results discussed herein serve as the first forays into understanding and characterizing the chemical behavior, on which more in depth work can be based.