title: Structure and phase transitions at the interface between α-Al2O3 and Pt.
abstract: The structure and thermodynamics of interfaces between (111) Pt and the basal plane of α-Al2O3 have been studied through a combination of high-resolution electron microscopy and first-principles calculations. Within the framework of ab initio thermodynamics the structure and excess free energies are calculated as functions of temperature (T) and oxygen partial pressure (PO2), for three competing interface terminations. Comparisons between measurements and calculations establish that the interface is oxygen terminated, and a structural phase transition is predicted in the range of experimentally accessible T and PO2 from the calculated interfacial free energies.
authors.affiliation: National Center for Electron Microscopy, Lawrence Berkeley National Laboratory, Berkeley, CA, USA. cophus@gmail.com
authors.forename: Colin
authors.initials: C
authors.lastname: Ophus
authors.forename: Melissa K
authors.initials: MK
authors.lastname: Santala
authors.forename: Mark
authors.initials: M
authors.lastname: Asta
authors.forename: Velimir
authors.initials: V
authors.lastname: Radmilovic