Local Coordination of Protons in In- and Sc-Doped BaZrO3
Journal article, 2019

Acceptor-doped barium zirconate-based proton conductors are currently receiving considerable attention because of their promise as electrolytes in future electrochemical devices, such as solid oxide fuel cells, but the defect chemistry, especially in regard to the local coordination environment and dynamics of protons in these materials, is unclear. Here, we investigate the local coordination environments and vibrational dynamics of protons in samples of the proton conducting material BaZr1-xMxO3Hx with M = In and Sc, and x = 0.1 and 0.5, using inelastic neutron scattering (INS), infrared (IR), and Raman spectroscopy together with ab initio molecular dynamics (AIMD) simulations. The local coordination of protons is shown to exhibit a rather peculiar dependence on the type and concentration of dopant atoms, as they are found to be similar for BaZr1-xScxO3Hx with x = 0.1 and 0.5 and BaZr1-xInxO3Hx with x = 0.1, whereas for BaZr1-xInxO3Hx with x = 0.5 additional proton sites seem to be present. It is argued that these additional proton sites are characterized by local structural arrangements reminiscent of the fully In-substituted material BaInO3H. The presence of these local structural arrangements points toward different local proton mobilities between BaZr1-xInxO3Hx with x = 0.5 and the other three materials and a higher rate of proton transfer events in brownrnillerite-type local structures.

Neutron scattering

Molecular dynamics

Solid oxide fuel cells (SOFC)

Barium zirconate

Author

Laura Mazzei

Chalmers, Chemistry and Chemical Engineering, Energy and Material

Adrien Perrichon

Chalmers, Chemistry and Chemical Engineering, Energy and Material

Alessandro Mancini

Universita degli studi di Pavia

Lorenzo Malavasi

Universita degli studi di Pavia

S. F. Parker

STFC Rutherford Appleton Laboratory

Lars Börjesson

Chalmers, Physics, Materials Physics

Maths Karlsson

Chalmers, Chemistry and Chemical Engineering, Energy and Material

Journal of Physical Chemistry C

1932-7447 (ISSN) 1932-7455 (eISSN)

Vol. 123 43 26065-26072

Subject Categories

Inorganic Chemistry

Materials Chemistry

Condensed Matter Physics

DOI

10.1021/acs.jpcc.9b07074

More information

Latest update

9/25/2020