Oxygen Diode Formed in Nickelate Heterostructures by Chemical Potential Mismatch

Guo, Erjia; Liu, Yaohua; Sohn, Changhee; Desautels, Ryan D.; Herklotz, Andreas; Liao, Zhaoliang; Nichols, John A.; Freeland, John; Fitzsimmons, Michael R.; Lee, Ho Nyung

doi:10.1002/adma.201705904

Title: Oxygen Diode Formed in Nickelate Heterostructures by Chemical Potential Mismatch

Journal Article · Wed Mar 07 00:00:00 EST 2018 · Advanced Materials

DOI:https://doi.org/10.1002/adma.201705904· OSTI ID:1430611

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Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Materials Science & Technology Division, and Neutron Scattering Division
Argonne National Lab. (ANL), Argonne, IL (United States). Advanced Photon Source (APS)
Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Materials Science & Technology Division, and Neutron Scattering Division; Univ. of Tennessee, Knoxville, TN (United States). Dept. of Physics and Astronomy

Deliberate control of oxygen vacancy formation and migration in perovskite oxide thin films is important for developing novel electronic and iontronic devices. Here in this paper, it is found that the concentration of oxygen vacancies (V_O) formed in LaNiO₃ (LNO) during pulsed laser deposition is strongly affected by the chemical potential mismatch between the LNO film and its proximal layers. Increasing the V_O concentration in LNO significantly modifies the degree of orbital polarization and drives the metal-insulator transition. Changes in the nickel oxidization state and carrier concentration in the films are confirmed by soft X-ray absorption spectroscopy and optical spectroscopy. The ability to unidirectional-control the oxygen flow across the heterointerface, e.g., a so-called oxygen diode, by exploiting chemical potential mismatch at interfaces provides a new avenue to tune the physical and electrochemical properties of complex oxides.

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Research Organization:: Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States); Argonne National Laboratory (ANL), Argonne, IL (United States)

Sponsoring Organization:: USDOE Office of Science (SC), Basic Energy Sciences (BES)

Grant/Contract Number:: AC05-00OR22725; AC02-06CH11357

OSTI ID:: 1430611

Alternate ID(s):: OSTI ID: 1424519; OSTI ID: 1466314

Journal Information:: Advanced Materials, Vol. 30, Issue 15; ISSN 0935-9648

Publisher:: WileyCopyright Statement

Country of Publication:: United States

Language:: English

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Cited by: 36 works

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Large orbital polarization in nickelate-cuprate heterostructures by dimensional control of oxygen coordination Liao, Zhaoliang; Skoropata, Elizabeth; Freeland, J. W. Nature Communications, Vol. 10, Issue 1 https://doi.org/10.1038/s41467-019-08472-y	journal	February 2019
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Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
36 MATERIALS SCIENCE
ionic rectification
nickelates
orbital polarization
oxygen diode
oxygen vacancies
optical conductivity
oxygen stoichiometry
x-ray absorption