Defect chemistry and electrical conductivity of Sm-doped La1−xSrxCoO3−δ for solid oxide fuel cells

Mårten E. Björketun, Ivano E. Castelli, Jan Rossmeisl, Thomas Olsen, Kenji Ukai,  Michiaki Kato, Gilles Dennler, and Karsten W. Jacobsen

J. Phys. Chem C 121, 15017-15027 (2017). DOI: 10.1021/acs.jpcc.7b02608

Description

We have calculated the electrical conductivity of the SOFC cathode contact material La1−xSrxCoO3−δ at 900 K. Experimental trends in conductivity against x, and against δ for fixed x, are correctly reproduced. Furthermore, we have studied the chemistry of neutral and charged intrinsic and extrinsic defects (dopants) in La0.5Sr0.5CoO3 and calculated the conductivity of the doped systems. In particular, we find that doping with Sm on the La site should enhance the conductivity, a prediction that is subsequently confirmed by electrical conductivity measurements.

The Database

The database contains all the investigated perovskite structures and the reference energies used to calculate the stability of the candidate materials.

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Key-value pairs: Description
project: Name of the project: "LSCO_conductivity"
name: Name of the structure
nLa: Number of La atoms
nSr: Number of Sr atoms
nCo: Number of Co atoms
nO: Number of O atoms
nDOP: Number of dopant atoms
dopant: chemical element of the dopant atom(s)
nvo: Number of O vacancies
conf: Configuration for the LSCO perovskites or "refs" for the reference systems used to calculate the stability
sigma: Value of sigma

Conductivity of LSCO

The script available here plots the conductivity as a function of the Sr content for the La1−xSrxCoO3−δ perovskites.

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Supporting Information

We add here some information regarding the manuscript. In particular, we show here the calculated formation free energies of vacancies (interstitials/anti-sites) in different charge states as a function of Fermi-level position within the theoretical band gap of La0.5Sr0.5CoO3:

  • vacancies

  •  interstitials

  • anti-sites