Graduate Research Assistant, University of Tennessee, Knoxville
Email address: [email protected]
Presented: November 19 and 20, 2020
“High Entropy Oxides: The Multicomponent Materials, Their Synthesis, and Properties”
Reports on the unique properties achieved with HEAs, including improved mechanical properties, has motivated the application of the multi-component approach to oxide materials, expanding the available compositional space and providing greater flexibility to meet the demands of today’s advanced materials. Since the first report in 2015, High Entropy Oxides (HEOs) have gained interest from a variety of fields as they provide opportunities for designing novel materials and tuning their properties. This will cover background information on the development of the material class and provide a comprehensive overview of our completed work including successful methods of synthesis, and notable properties investigated. A comparison of synthesis methods has been done for some compositions showing polymeric steric entrapment, a polymer assisted wet chemistry method, to be advantageous in HEOs when compared to the traditional solid-state method. A broad range of compositions and crystal structures, including perovskite, spinel, and Ruddleson Popper, have been successfully made. The effects of multicomponent material design on the structural, magnetic, and chemical properties are explored. In order to compare synthesis methods and gain insight in the kinetics involved, we have also employed rapid in-situ non-ambient X-ray diffraction to characterize the phase transformation and evolution of crystallinity in HEO materials.
Brianna L. Musicó, Graduate Research Assistant, University of Tennessee, Knoxville
Brianna Musicó is a fifth-year graduate student in the Materials Science and Engineering (MSE) Department at the University of Tennessee, Knoxville (UTK) with an expected graduation spring/summer 2021. Brianna received her B.S. in August of 2016 and her M.S. in December of 2018 both in materials science and engineering from the University of Tennessee. Brianna is currently working under the direction of Veerle Keppens, Ph.D. focusing on the synthesis and characterization of high entropy oxides. Multicomponent, high entropy, systems have been investigated for their variety of physical properties achieved by forming new phases. This type of research has been done on many metallic alloy systems (HEAs) but has recently been expanded into ceramic systems by creating configurational disorder into a sublattice of a mixed oxide to form a high entropy oxide (HEO). These classes of materials are of interest as they have potential for multi-functionality. Brianna is focused predominately on spinel and perovskite type HEO systems, synthesizing single phase materials, and investigating their phase formation, structure, and magnetic properties. Her research also involves the use of resonant ultrasound spectroscopy (RUS) for elastic moduli property determination and has participated in many collaborations measuring these properties on other material systems. In 2019 she was selected as the Highlighted Graduate Student for the Center for Materials Processing, a Tennessee Higher Education Commission (THEC) supported Accomplished Center of Excellence. In the summer of 2020, she was selected as a recipient of a 12-month support package through the Center for Materials Processing Graduate Student Support Program. Brianna was the 2017-2018 vice president for the UTK chapter of the Materials Research Society, served as the 2018-2019 president, and was the recipient of the 2018 UTK MSE Graduate Student Service Award.