Scott Barnett, Northwestern University (1 of 2)

Connecting 3D Microstructure with SOFC Electrode Performance

The performance of SOFC electrodes depends heavily on the electrode microstructures. However, characteristics such as the TPB density, phase tortuosity, and phase connectivity are inherently described in three dimensions and hence are difficult to measure from 2D cross-sectional images. Here we show quantitative 3D microstructural analysis of a number of different electrode material systems using a FIB-SEM serial-sectioning technique. A series of LSM-YSZ cathodes were fabricated with varying LSM:YSZ ratio. The performance of the electrodes was found to rely heavily on the electrochemically active TPB (EA-TPB) density, a function of the level of connectivity of the LSM and YSZ phases, as well as on the YSZ tortuosity. A series of Ni-YSZ anodes were also processed with different Ni:YSZ ratios and poor performance at low Ni content was found to be a result of high levels of isolated Ni.

Reconstructed microstructures also serve as inputs for electrochemical and kinetic models. Experimentally obtained microstructures of Ni-YSZ anodes that underwent accelerated coarsening were obtained and compared with phase-field modeling in order to estimate Ni diffusion rates under normal operating conditions. Lastly, results from LSC single-phase cathodes and LSCF nano-particle infiltrated cathodes will be presented.

Symposium on Solid oxide cell electrodes in 3D

Category:

Science & Technology

Tags:

• SOFC
• FIB-SEM
• Tomography
• 3D
• microstructure
• Northwestern University
• James WIlson
• Scott Barnett
• Scott Cronin

[mehdiyt]

is there any publication based on this lecture?