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Title: Layer-by-layer epitaxial growth of defect-engineered strontium cobaltites

Abstract

Here, control over structure and composition of (ABO 3) perovskite oxides offers exciting opportunities since these materials possess unique, tunable properties. Perovskite oxides with cobalt B-site cations are particularly promising, as the range of the cation’s stable oxidation states leads to many possible structural frameworks. Here, we report growth of strontium cobalt oxide thin films by molecular beam epitaxy, and conditions necessary to stabilize different defect concentration phases. In situ X-ray scattering is used to monitor structural evolution during growth, while in situ X-ray absorption near-edge spectroscopy is used to probe oxidation state and measure changes to oxygen vacancy concentration as a function of film thickness. Experimental results are compared to kinetically-limited thermodynamic predictions, in particular, solute trapping, with semi-quantitative agreement. Agreement between observations of dependence of cobaltite phase on oxidation activity and deposition rate, and predictions indicates that a combined experimental/theoretical approach is key to understanding phase behavior in the strontium cobalt oxide system.

Authors:
ORCiD logo [1];  [1];  [2];  [2];  [3];  [2]
  1. Argonne National Lab. (ANL), Argonne, IL (United States); Northwestern Univ., Evanston, IL (United States)
  2. Argonne National Lab. (ANL), Argonne, IL (United States)
  3. Northwestern Univ., Evanston, IL (United States)
Publication Date:
Research Org.:
Argonne National Lab. (ANL), Argonne, IL (United States)
Sponsoring Org.:
USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC-22)
OSTI Identifier:
1417645
Grant/Contract Number:
AC02-06CH11357
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
ACS Applied Materials and Interfaces
Additional Journal Information:
Journal Name: ACS Applied Materials and Interfaces; Journal ID: ISSN 1944-8244
Publisher:
American Chemical Society (ACS)
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; perovskite; thin film; oxide; cobaltite; epitaxy; metal oxides; strontium cobalt oxide; molecular beam epitaxy; defects in oxides; perovskite oxides; thin films

Citation Formats

Andersen, Tassie K., Cook, Seyoung, Wan, Gang, Hong, Hawoong, Marks, Laurence D., and Fong, Dillon D. Layer-by-layer epitaxial growth of defect-engineered strontium cobaltites. United States: N. p., 2018. Web. doi:10.1021/acsami.7b16970.
Andersen, Tassie K., Cook, Seyoung, Wan, Gang, Hong, Hawoong, Marks, Laurence D., & Fong, Dillon D. Layer-by-layer epitaxial growth of defect-engineered strontium cobaltites. United States. doi:10.1021/acsami.7b16970.
Andersen, Tassie K., Cook, Seyoung, Wan, Gang, Hong, Hawoong, Marks, Laurence D., and Fong, Dillon D. 2018. "Layer-by-layer epitaxial growth of defect-engineered strontium cobaltites". United States. doi:10.1021/acsami.7b16970.
@article{osti_1417645,
title = {Layer-by-layer epitaxial growth of defect-engineered strontium cobaltites},
author = {Andersen, Tassie K. and Cook, Seyoung and Wan, Gang and Hong, Hawoong and Marks, Laurence D. and Fong, Dillon D.},
abstractNote = {Here, control over structure and composition of (ABO3) perovskite oxides offers exciting opportunities since these materials possess unique, tunable properties. Perovskite oxides with cobalt B-site cations are particularly promising, as the range of the cation’s stable oxidation states leads to many possible structural frameworks. Here, we report growth of strontium cobalt oxide thin films by molecular beam epitaxy, and conditions necessary to stabilize different defect concentration phases. In situ X-ray scattering is used to monitor structural evolution during growth, while in situ X-ray absorption near-edge spectroscopy is used to probe oxidation state and measure changes to oxygen vacancy concentration as a function of film thickness. Experimental results are compared to kinetically-limited thermodynamic predictions, in particular, solute trapping, with semi-quantitative agreement. Agreement between observations of dependence of cobaltite phase on oxidation activity and deposition rate, and predictions indicates that a combined experimental/theoretical approach is key to understanding phase behavior in the strontium cobalt oxide system.},
doi = {10.1021/acsami.7b16970},
journal = {ACS Applied Materials and Interfaces},
number = ,
volume = ,
place = {United States},
year = 2018,
month = 1
}

Journal Article:
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