Date(s) - 14 Feb 2019
3:00 PM - 4:00 PM
2155 Marston Hall
Speaker: Christina Rost, Postdoctoral Research Associate with the Department of Mechanical and Aerospace Engineering at the University of Virginia
Title: Entropy-Stabilized Oxides: A New Paradigm for Materials Exploration
Abstract: The current scientific challenges in developing new materials, to meet the ever-increasing demands of technological innovation, opens the door to complex structure-property relationships awaiting exploration. Entropy-stabilized oxides (ESOs) are a novel class of multicomponent materials, that demonstrate the viability of materials engineering using configurational entropy to drive phase stabilization. Through a rigorous set of experiments and a five-component oxide formulation, it is demonstrated that entropy predominates the thermodynamic landscape, and drives a reversible solid-state transformation between a multiphase and single-phase state. The findings validate the hypothesis that deliberate configurational disorder provides an alternative strategy to materials discovery and untapped opportunities for property engineering. To date, ESOs are gaining significant traction in the materials community, as unique and interesting properties and applications are revealed, such as colossal dielectric constants, superionic conductivity, amorphous-like thermal conductivities, and thermochemical water splitting. This presentation highlights the scientific journey of ESOs with a focus on the experimental process of elimination using several metrology techniques in conjunction with modeling to gain meaningful perspective on configurationally disordered, highly crystalline systems. Entropic stabilization, thermal property studies, and the potential for additional technological applications are discussed.
Bio: Dr. Tina Rost graduated with a Ph.D. in Materials Science and Engineering from North Carolina State University in 2016, following both a B.S. and an M.S. in Physics from Indiana University of Pennsylvania. Her Ph.D. focused on the development and phase-characterization of a novel class of oxide systems stabilized through configurational disorder, named “Entropy Stabilized Oxides”. Tina is currently a Postdoctoral Research Associate in the Experiments and Simulations in Thermal Engineering (ExSITE) group, within the Department of Mechanical and Aerospace Engineering at the University of Virginia. Here, her work focuses on experimental methods to test thermal properties at extremely high temperatures and thermal transport in complex and high-entropy oxides and carbides.
MSE Seminar Host: Katie Bratlie