Vibrational Properties of Protons in Hydrated BaInxZr1-xO3-x/2
Journal article, 2005

We investigate the local proton dynamics in the proton conducting hydrated perovskite system BaInxZr1-xO3-x/2 (x=0.25-0.75) using infrared spectroscopy and first-principles calculations. We show that oxygen vacancies and dopant atoms in the vicinity of the proton tilt the proton toward a neighboring oxygen creating strongly hydrogen-bonded configurations. This is manifested as a strong redshift of the O-H stretch band in the infrared absorption spectrum. We also find considerable fluctuations of the nearest and next-nearest oxygen-proton distances with time, resulting in additional spectral broadening. By comparing the frequencies of computed O-H stretch modes we can relate specific local configurations to different parts of the broad O-H stretch band. Even though hydrogen-bonded configurations favor proton transfer they hinder the long-range migration by decreasing the reorientational rate. Thus, in order to optimize the proton mobility it is important to avoid extreme configurations caused by either oxygen vacancies or dopant atoms in the perovskite structure.

Author

Maths Karlsson

Chalmers, Applied Physics

Mårten Björketun

Chalmers, Applied Physics, Materials and Surface Theory

Per G. Sundell

Chalmers, Applied Physics, Materials and Surface Theory

Aleksandar Matic

Chalmers, Applied Physics

Göran Wahnström

Chalmers, Applied Physics, Materials and Surface Theory

Dennis Engberg

Chalmers, Applied Physics, Condensed Matter Physics

Lars Börjesson

Chalmers, Applied Physics, Condensed Matter Physics

Istaq Ahmed

Chalmers, Chemical and Biological Engineering

Sten Eriksson

Chalmers, Chemical and Biological Engineering

Pedro Berastegui

Chalmers, Chemical and Biological Engineering

Physical Review B - Condensed Matter and Materials Physics

1098-0121 (ISSN)

Vol. 72 1-7

Subject Categories

Condensed Matter Physics

DOI

10.1103/PhysRevB.72.094303

More information

Created

10/7/2017