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Updated: Dec 1, 2025
Tuning Oxide Properties by Oxygen Vacancy Control During Growth and Annealing
Published on: June 9, 2023
Conceptual Framework for Dislocation-Modified Conductivity in Oxide Ceramics Deconvoluting Mesoscopic Structure,
Lukas Porz1, Till Frömling1, Atsutomo Nakamura2,3
1Department of Materials and Earth Science, Technical University of Darmstadt, Alarich-Weiss-Straße 2, 64287 Darmstadt, Germany.
Abstract:
The introduction of dislocations is a recently proposed strategy to tailor the functional and especially the electrical properties of ceramics. While several works confirm a clear impact of dislocations on electrical conductivity, some studies raise concern in particular when expanding to dislocation arrangements beyond a geometrically tractable bicrystal interface. Moreover, the lack of a complete classification on pertinent dislocation characteristics complicates a systematic discussion and hampers the design of dislocation-modified electrical conductivity. We proceed by mechanically introducing dislocations with three different mesoscopic structures into the model material single-crystal SrTiO3 and extensively characterizing them from both a mechanical as well as an electrical perspective. As a final result, a deconvolution of mesoscopic structure, core structure, and space charge enables us to obtain the complete picture of the effect of dislocations on functional properties, focusing here on electric properties.
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