|About this Abstract
||MS&T23: Materials Science & Technology
||Grain Boundaries, Interfaces, and Surfaces: Fundamental Structure-Property-Performance Relationships
||Highly Conductive Grain Boundaries in Cold Sintered BaZr0.7Ce0.2Y0.1O3-δ Proton Conductors
||Moritz Kindelmann, Sonia Escolastico, Laura Almar, Ashok Vayalla, Dylan Jennings, Wendelin Deibert, Wilhelm Albert Meulenberg, Wolfgang Rheinheimer, Martin Bram, Jose Serra, Joachim Mayer, Olivier Guillon
|On-Site Speaker (Planned)
Proton conducting ceramics based on yttrium doped barium cerium zirconate (BaZr1-xCexY0.1O3-δ, BZCY) have a great potential for intermediate temperature energy conversion applications. However, the electrochemical performance of proton conducting perovskites is highly dependent on their microstructure and the associated grain boundary properties. Here, we present a novel low temperature processing route for BZCY electrolytes using the cold sintering process (CSP) combined with an intermediate thermal treatment, that yields nano-scaled microstructures, which strongly differ from conventionally processed BZCY. However, the protonic conductivity could be improved compared to conventionally processed samples. Therefore, the structure and chemistry at grain boundaries was characterized using aberration corrected transmission electron microscopy and atom probe tomography and correlated with the electrochemical properties. Lowering the processing temperatures clearly changes the segregation behavior and elemental distribution of Y dopants and Ni sintering aids at the grain boundary, explaining the major changes in protonic conductivity observed at the macroscopic level.