*********************************
There is now a CONTENT FREEZE for Mercury while we switch to a new platform. It began on Friday, March 10 at 6pm and will end on Wednesday, March 15 at noon. No new content can be created during this time, but all material in the system as of the beginning of the freeze will be migrated to the new platform, including users and groups. Functionally the new site is identical to the old one. webteam@gatech.edu
*********************************
THE SCHOOL OF MATERIALS SCIENCE AND ENGINEERING
GEORGIA INSTITUTE OF TECHNOLOGY
Under the provisions of the regulations for the degree
DOCTOR OF PHILOSOPHY
on Friday, July 26, 2019
1:30 PM
in MoSE 3201A
will be held the
DISSERTATION DEFENSE
for
Ryan Joe Murphy
"A New Family of Proton Conducting Electrolytes with Enhanced Stability for Reversable Fuel Cell Operation: BaHfxCe0.8-xY0.1Yb0.1O3"
Committee Members:
Prof. Meilin Liu, Advisor, MSE
Prof. Hamid Garmestani, MSE
Prof. Preet Singh, MSE
Prof. Mark Losego, MSE
Prof. Angus Wilkinson, Chemistry
Abstract:
Solid oxide fuel cell (SOFC) technology has the potential to be one of the most efficient energy conversion technologies and the same technology can be used to efficiently produce several chemical species such as hydrogen and syngas through reverse operation, known as solid oxide electrolysis cells (SOEC). However, the long-term performance of these systems is often limited by degradation of the electrolyte. In order to address the degradation issues, this work has developed a new family of proton conducing electrolyte materials, BaHfxCe0.8-xY0.1Yb0.1O3 (BHCYYb), which demonstrates much improved stability while maintaining similar or higher conductivities than current state-of-the-art materials. This resulted in SOFC performance which rivals that of the current best performance reported in literature, but with better durability. In addition to its success as an electrolyte for hydrogen operation, BHCYYb has been shown to possess higher stability through long term chemical stability and long-term conductivity tests. To take advantage of the higher stability, long term tests of cells fabricated with BHCYYb were tested as reversible fuel cells as well as SOECs for CO2-H2O co-electrolysis. Finally, the performance of BHCYYb was attempted to be further improved by studying novel dopants in the BaHfO3 system.
