DISSERTATION DEFENSES
During the time of COVID19 as the world came to a crashing halt, Universities, students, faculty and staff had to persevere and continue on our research mission; including holding dissertation defenses via Zoom. The human spirit is a magical thing and even during the riptide of the unknown, graduate students at The University of Texas at Austin shine bright. We've chosen to share some of our outstanding graduate student defense talks that were recorded via Zoom so our Longhorns can show that What Happens Here - truly does - Change The World.
Please feel free to visit the Box link below to access the following talks:
https://utexas.box.com/v/DissertationDefenses
Introducing:
Dr. Jamie Trindell
The use of well-defined nanoparticle (NP) systems provides the opportunity to experimentally test and validate theoretical predictions. My work addresses the experimental limitations that persist at the juncture between theory and electrocatalysis. First, the area of NP stability remains largely untouched by computational chemists. This is largely due to the computationally intractable nature of ligands, which affect the experimentally observed stability of NP systems. The ability to experimentally understand NP stability will continue to provide insight into progressing theoretical advancements in this area. To this end, I describe the use of ex situ scanning transmission electron microscopy (STEM) to analyze the growth of AuNPs during electrocatalytic CO2 reduction, highlighting the importance of catalyst characterization both before and after electrochemical measurements, especially in relation to theoretical models.
Another area that my work addresses is the experimental validation of theoretical predictions and concepts. The ability to both rule-in and rule-out potential catalysts based on theoretical models holds the key for truly allowing theory to guide experiment. Altogether, my graduate research aims to lessen the gap between theory and experiment in the field of electrocatalysis.
Dr. Aliya Lapp
In this defense, experiment and theory are combined to investigate Pt electrodeposition onto ~1-2 nm Au dendrimer-encapsulated nanoparticles (DENs) using three different techniques: the hydride-terminated (HT) method, Cu underpotential deposition followed by Pt galvanic exchange (Cu UPD/Pt GE), and Pb UPD/Pt GE. We find that these three techniques generate AuPt nanoparticle (NP) structures that are dissimilar to one another and to the corresponding structures for bulk Au substrates. We focus on the HT method, as the AuPt alloy NP structure formed using that method laid the foundation for the other two techniques. After monolayer techniques are discussed, we briefly describe our study of the electrodeposition of multiple Pt layers onto Au DENs using successive iterations of the HT method.
Dr. Collin Davies
The separation of chemical mixtures into pure and purer constituents is essential to humankind. However, the most common techniques for chemical separations are energy intensive and improvements in their efficiency are only incremental. To meet the rising demands of an ever-increasing global population, new techniques that separate chemicals on the basis of phenomena fundamentally different than that of the existing methods must be developed. To that end, we set out nearly five years ago with the goal to continuously separate charged objects within ion depletion zones formed by electrochemical processes in microfluidic channels. So far, we have performed experimental and computational studies to describe the processes fundamental to controlling the flow of charged objects with ion depletion zones and the corresponding electric field gradients. Future research will seek to develop additional electrochemical methods to form ion depletion zones in solution and extend these findings to other types of chemical separations.
