Abstract
Engineering oxygen vacancy formation and distribution is a powerful route for controlling the oxygen sublattice evolution that affects diverse functional behavior. The controlling of the oxygen vacancy formation process is particularly important for inducing topotactic phase transitions that occur by transformation of the oxygen sublattice. Here we demonstrate an epitaxial nanocomposite approach for exploring the spatial control of topotactic phase transition from a pristine perovskite phase to an oxygen vacancy-ordered brownmillerite (BM) phase in a model oxide La0.7Sr0.3MnO3 (LSMO). Incorporating a minority phase NiO in LSMO films creates ultrahigh density of vertically aligned epitaxial interfaces that strongly influence the oxygen vacancy formation and distribution in LSMO. Combined structural characterizations reveal strong interactions between NiO and LSMO across the epitaxial interfaces leading to a topotactic phase transition in LSMO accompanied by significant morphology evolution in NiO. Using the NiO nominal ratio as a single control parameter, we obtain intermediate topotactic nanostructures with distinct distribution of the transformed LSMO-BM phase, which enables systematic tuning of magnetic and electrical transport properties. The use of self-assembled heterostructure interfaces by the epitaxial nanocomposite platform enables more versatile design of topotactic phase structures and correlated functionalities that are sensitive to oxygen vacancies.[Figure not available: see fulltext.]
Original language | English |
---|---|
Article number | 2 |
Journal | Nano-Micro Letters |
Volume | 14 |
Issue number | 1 |
DOIs | |
State | Published - Dec 2022 |
Funding
This work was supported by the US Department of Energy (DOE), Office of Science, Basic Energy Sciences (BES), Materials Sciences and Engineering Division. Part of this research was performed at the Center for Nanophase Materials Sciences at Oak Ridge National Laboratory, which is a DOE Office of Science User Facility. The electron microscopy work done at Brookhaven National Laboratory was supported by the U.S. DOE-BES, the Center for Functional Nanomaterials, a DOE Office of Science User Facility, and Materials Science and Engineering Division, under Contract No. DE-SC0012704. W. Z. acknowledges the support by National Natural Science Foundation of China (Grant No. 62004200) and Zhejiang Provincial Natural Science Foundation (Grant No. LZ21F040001). S. C. acknowledges the support by Q-MEEN-C, an Energy Frontier Research Center funded by the U.S. DOE-BES under award No. DE-SC0019273.
Funders | Funder number |
---|---|
U.S. DOE-BES | |
U.S. Department of Energy | |
Office of Science | |
Basic Energy Sciences | |
Division of Materials Sciences and Engineering | DE-SC0012704 |
National Natural Science Foundation of China | 62004200 |
Natural Science Foundation of Zhejiang Province | LZ21F040001, DE-SC0019273 |
Keywords
- Epitaxial interface
- Functional oxides
- Nanocomposite
- Oxygen vacancy
- Topotactic phase transition