CHEE Seminar: Xiaodan Gu
Monday, November 15, 2021 – 3 PM
Xiaodan Gu
Assistant Professor
School of Polymer Science and Engineering
University of Southern Mississippi
"Design strategies to predict and control semiconducting polymers’ dynamics"
Zoom link: https://arizona.zoom.us/j/84145629239
ABSTRACT
Organic semiconducting polymers were widely studied due to their unique optoelectronic and mechanical property. They are the key component in various functional electronic devices, such as organic photovoltaic devices, flexible displays, wearable sensors, neuromorphic computing, and more recently bioelectronics. Despite tremendous progress being made in improving the charge carrier mobility and optimizing energy bandgap, the conjugated polymer's physical property was not widely studied such as chain rigidly, molecular entanglement behavior, and glass transition phenomenon. However, they are important for device stability, which is one of the major hurdles for polymer-based organic devices. Polymer dynamics could play an important role in dictating overall chain mobility and morphology stability in the bulk heterojunction.
In my talk, I will provide an overview of our effort in studying the conjugated polymer's dynamics using a wide range of unique characterization tools, from thin-film to bulk. I will discuss the challenge associated with accurately measuring the glass transition temperature for rigid conjugated polymers. I will discuss our approach to address this challenge using thin-film calorimetry and ellipsometry tools, as well as using molecular dynamic simulation and cheminformatic to accurately predict the glass transition temperature. Lastly, I will discuss how dynamics could impact thin film morphology and device performance at different operation temperatures and should be carefully considered when designing new polymers and devices.
BIOSKETCH
Xiaodan Gu earned his Ph.D. from the Department of Polymer Science and Engineering at the University of Massachusetts Amherst in 2014, focusing on the self-assembly of block copolymers and their lithographic applications. Subsequently, he did a post-doctoral at the Stanford University and SLAC National Accelerator Laboratory, where he studied the morphology of roll-to-roll printed electronics using real-time X-ray scattering at various synchrotron beamlines. He is currently a Nina Bell Suggs Endowed assistant professor from the School of Polymer Science and Engineering at the University of Southern Mississippi. His current research interests revolve around various fundamental polymer physics phenomena related to conjugated polymers and their derivative devices. His group studies the structure, dynamics, and morphology of conjugated polymers and aims to link their molecular structures to their macroscopic properties through advanced metrology with an emphasis on scattering techniques. His research team’s effort was recognized by the NSF Career Award, DOE Early Career Award, ACS PMSE Young Investigator Award and ORAU Powe Junior Faculty Enhancement Award.