CHEMSEM 13: April 22, 2021
Development of Novel Conductive Transparent Materials
The faculty, students and staff of the Andrews University Department of Chemistry & Biochemistry are pleased to invite all to view a Zoom lecture by K. Andre Mkhoyan, PhD, on Thursday, April 22, 2021, at 4:30 p.m. EST on "Development of Novel Conductive Transparent Materials."
This is the thirteenth installment of the Dwain L. Ford Lecture Series in the Andrews University Department of Chemistry & Biochemistry 2021 spring seminar program. Everyone is invited to view the lecture at https://andrews.zoom.us/j/97156680893. The meeting ID is 971 5668 0893.
Teachers are encouraged to announce this lecture in their classes and/or forward this email to their classes. Please share and encourage your colleagues, friends and others to tune in online. This lecture is free and open to all: students, high school through college, and everyone in our community and general public.
The Dwain L. Ford Lecture Series is co-sponsored by the Andrews University Office of Research & Creative Scholarship, Berrien RESA Math Science Center and the Chemistry Honors Society.
Seminar Zoom Protocol:
- Mute your sound.
- Everyone can ask/write a question in the chat.
Abstract:
While working on understanding line defects in perovskite crystals, we made a discovery of fascinating material phenomena, formation of non-conventional line defect in perovskite crystal, which is neither dislocation nor disclination. What is remarkable about this new line defect is that even though compositionally the defect is an oxide (SnmOn) located inside insulating wide-bandgap (Eg = 3 eV) BaSnO3 perovskite crystal, it is metallic. DFT-based analysis, also discussed here, explains the origin of this phenomena. Considerably different coordination and bonding angles of the atoms in the defect core dramatically modify the local electronic band structure pushing electronic stated from the core Sn and O atoms above the material Fermi energy making it metallic. These observations can have lasting effects on how we think and engineer metallic behaviors in insulating perovskite. Another interesting observation from this study is that these line defects propagate along film growth direction, which is a sign of being controllable for engineering purposes. Study of line defects in oxide perovskite is essential for proper understanding of ion gel gating and possible conduction and carrier scattering mechanisms in these materials.
Speaker’s Bio:
Mkhoyan is the Ray D. and Mary T. Johnson Chair Professor in the Department of Chemical Engineering and Materials Science at the University of Minnesota, Twin Cities. He graduated from Yerevan State University with a BS in physics in 1996. From 1998 to 1999 he worked as a researcher at Bell Labs of Lucent Technologies in Murray Hill, New Jersey. He then received a PhD in 2004 at Cornell University in applied physics. From 2004 to 2008 he was a post-doctoral research associate at Cornell and visiting scientist at the IBM T.J. Watson Research Center. He joined the University of Minnesota in 2008 as an assistant professor.
PR
pr@andrews.edu
