| About this Abstract |
| Meeting |
MS&T24: Materials Science & Technology
|
| Symposium
|
Grain Boundaries, Interfaces, and Surfaces: Fundamental Structure-Property-Performance Relationships
|
| Presentation Title |
Local Cationic Ordering in Iron-Substituted Strontium Titanate |
| Author(s) |
Dylan Jennings, M. Pascal Zahler, Moritz Kindelmann, Franziska E. Winterhalder, Di Wang, Olivier Guillon, Joachim Mayer, Wolfgang Rheinheimer |
| On-Site Speaker (Planned) |
Dylan Jennings |
| Abstract Scope |
Iron-substituted strontium titanate (STF) is a model perovskite oxide which has potential for use in energy applications thanks to its mixed oxygen and electronic conductivity. Cationic segregation at defects can significantly impact material properties, for example through the modification of space charge zones at grain boundaries, or through alterations in local atomic structure. In this work, local cationic ordering in STF is explored through scanning transmission electron microscopy. Cationic segregation at grain boundaries is examined as the bulk iron content is increased up to 25 at% on the B-site. In addition to grain boundary effects, bulk ordering is characterized in materials with higher Fe contents (e.g. 50 at% Fe on the B-site), showing that planar defects form which adopt a quasi-brownmillerite structure. A discussion of cationic ordering over a wide compositional range is presented, with an additional focus on the impact of local ordering on material properties. |