Nanoscale Imaging Studies of Cobaltite Thin Films Using X-Ray Nanodiffraction

POSTER

Abstract

The perovskite (ABO3) and closely related brownmillerite (ABO2.5) phase of cobaltites possess a wide range of functional properties, which makes them promising candidates for solid oxide fuel cells, ionically-gated devices, and magneto-ionic devices. However, the role played by nanoscale morphology, i.e. phase separation and defects in these oxide thin films and heterostructures, remains unknown. This poster presents nanoscale imaging studies of emergent structural phases and their morphology in cobaltite heterostructures using x-ray nano-diffraction. Gd/La0.67Sr0.33CoO3 heterostructures were ionically and stoichiometrically controlled via the thickness of the Gd oxygen-gettering layers. Our measurements, using the hard x-ray nanoprobe at the Advanced Photon Source, show lateral and transverse nanoscale separation of the perovskite and brownmillerite phases. These nanoscale heterogeneities were characterized and strain mapped in real space with a spatial resolution of 25 nm. Our studies provide insights into the nanoscale morphology which can be utilized to tune the macroscopic functional properties of cobaltite heterostructures.

Presenters

  • Geoffery Ian Rippy

    Materials Science and Engineering, Uinversity of California, Davis, University of California, Davis, Materials Science and Engineering, University of California Davis

Authors

  • Geoffery Ian Rippy

    Materials Science and Engineering, Uinversity of California, Davis, University of California, Davis, Materials Science and Engineering, University of California Davis

  • Lacey L Trinh

    University of California, Davis, Materials Science and Engineering, University of California Davis

  • Alexander Michael Kane

    University of California, Davis, Materials Science and Engineering, University of California Davis, Materials Science and Engineering, University of California, Davis

  • Aleksey Ionin

    University of California, Davis, Materials Science and Engineering, University of California Davis

  • Michael Steven Lee

    University of California, Davis, Materials Science and Engineering, University of California Davis, Materials Science and Engineering, University of California, Davis

  • Rajesh V Chopdekar

    University of California, Davis, Materials Science and Engineering, University of California Davis, Advanced Light Source, Lawrence Berkeley National Laboratory, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA, LBNL Advanced Light Source

  • Dustin Gilbert

    National Institute of Standards and Technology, NIST Center for Neutron Research, NIST Gaithersburg, Department of Materials Engineering, University of Tennesse, Knoxville

  • Alexander Grutter

    National Institute of Standards and Technology, NIST, NIST Center for Neutron Research, NIST Gaithersburg, Neutron-Condensed Matter Science Group, NIST, NIST Center for Neutron Research

  • Peyton Murray

    University of California, Davis, Physics, University of California Davis

  • Martin Holt

    Argonne National Laboratory, Center for Nanoscale Materials, Argonne National Laboratory, Advanced Photon Source, Argonne National Laboratory

  • Zhonghou Cai

    Argonne National Laboratory, Advanced Photon Source, Argonne National Laboratory

  • Kai Liu

    University of California, Davis, Physics, University of California Davis

  • Yayoi Takamura

    University of California, Davis, Materials Science and Engineering, University of California Davis, Materials Science and Engineering, University of California, Davis

  • Roopali Kukreja

    Materials Science and Engineering, Uinversity of California, Davis, University of California, Davis, Materials Science and Engineering, University of California Davis