Cation and anion topotactic transformations in cobaltite thin films leading to Ruddlesden-Popper phases
Journal Article
·
· Physical Review Materials
- Univ. of California, Davis, CA (United States); University of California, Davis
- Univ. of California, San Diego, La Jolla, CA (United States)
- Brookhaven National Lab. (BNL), Upton, NY (United States)
- Univ. of Chicago, IL (United States)
- Univ. of California, Santa Barbara, CA (United States)
- Purdue Univ., West Lafayette, IN (United States)
- Univ. of California, Davis, CA (United States)
- Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)
- SLAC National Accelerator Lab., Menlo Park, CA (United States)
- Univ. of Chicago, IL (United States); Argonne National Lab. (ANL), Lemont, IL (United States)
Topotactic transformations involve structural changes between related crystal structures due to a loss or gain of material while retaining a crystallographic relationship. The perovskite oxide La0.7Sr0.3CoO3 (LSCO) is an ideal system for investigating phase transformations due to its high oxygen vacancy conductivity, relatively low oxygen vacancy formation energy, and strong coupling of the magnetic and electronic properties to the oxygen stoichiometry. While the transition between cobaltite perovskite and brownmillerite (BM) phases has been widely reported, further reduction beyond the BM phase lacks systematic studies. In this paper, we study the evolution of the physical properties of LSCO thin films upon exposure to highly reducing environments. We observe the rarely reported crystalline Ruddlesden-Popper phase, which involves the loss of both oxygen anions and cobalt cations upon annealing where the cobalt is found as isolated Co ions or Co nanoparticles. First-principles calculations confirm that the concurrent loss of oxygen and cobalt ions is thermodynamically possible through an intermediary BM phase. Furthermore, the strong correlation of the magnetic and electronic properties to the crystal structure highlights the potential of utilizing ion migration as a basis for emerging applications such as neuromorphic computing.
- Research Organization:
- Brookhaven National Laboratory (BNL), Upton, NY (United States); SLAC National Accelerator Laboratory (SLAC), Menlo Park, CA (United States); Univ. of California, Davis, CA (United States)
- Sponsoring Organization:
- USDOE Office of Science (SC), Basic Energy Sciences (BES)
- Grant/Contract Number:
- AC02-05CH11231; AC02-76SF00515; SC0012704; SC0019273
- OSTI ID:
- 1798563
- Alternate ID(s):
- OSTI ID: 1807947
OSTI ID: 1814034
OSTI ID: 1868556
- Report Number(s):
- BNL--221809-2021-JAAM
- Journal Information:
- Physical Review Materials, Journal Name: Physical Review Materials Journal Issue: 6 Vol. 5; ISSN 2475-9953
- Publisher:
- American Physical Society (APS)Copyright Statement
- Country of Publication:
- United States
- Language:
- English
Similar Records
Cation and anion topotactic transformations in cobaltite thin films leading to Ruddlesden-Popper phases.
Journal Article
·
Thu Jun 24 00:00:00 EDT 2021
· Physical Review Materials
·
OSTI ID:1868556
Related Subjects
75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
Cobaltite thin films
Crystal defects
Electrical conductivity
Electronic structure of atoms & molecules
Epitaxial strain
First-principles calculations
Magnetic oxides
Magnetism
Phase transitions
Ruddlesden-Popper
Topotactic transformations
SUPERCONDUCTIVITY AND SUPERFLUIDITY
Cobaltite thin films
Crystal defects
Electrical conductivity
Electronic structure of atoms & molecules
Epitaxial strain
First-principles calculations
Magnetic oxides
Magnetism
Phase transitions
Ruddlesden-Popper
Topotactic transformations