Characterization of 3D interconnected microstructural network in mixed ionic and electronic conducting ceramic
William M Harris1, Kyle S Brinkman, Ye Lin
1HeteroFoaM Center, a DOE Energy Frontier Research Center, USA. wchiu@engr.uconn.edu.
Nanoscale
|March 12, 2014
Summary
Microstructure analysis of composite ceramic membranes reveals an emergent phase impacting device performance. Understanding this phase is key for designing advanced materials under non-equilibrium conditions.
Area of Science:
- Materials Science
- Ceramic Engineering
- Nanotechnology
Background:
- The performance of composite ceramic membranes hinges on the microstructure and connectivity of their ionic and electronic conductive phases.
- Metal-Impregnated Ceramic (MIEC) composites are crucial for various electrochemical devices.
Purpose of the Study:
- To characterize the 3-D microstructure and composition of a GDC-CFO MIEC composite.
- To investigate the formation and distribution of an emergent phase within the composite.
- To correlate microstructural features with potential device performance.
Main Methods:
- Utilized Transmission Electron Microscopy (TEM) with chemical mapping.
- Employed X-ray Nanotomography (XNT) for 3-D microstructural analysis.
- Characterized a model system of Ce0.8Gd0.2O2 (GDC) and CoFe2O4 (CFO) phases.
Main Results:
- Detailed 3-D compositional and microstructural data of the GDC-CFO composite was obtained.
- Identified an emergent phase present as isolated, distinct regions within the microstructure.
- The distribution and composition of this emergent phase were analyzed.
Conclusions:
- The study provides critical insights into the complex microstructure of MIEC composites.
- The emergent phase's characteristics are significant for understanding material behavior.
- Findings inform the design of novel ceramic membrane systems for demanding operating conditions.
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