Quantifying percolated triple phase boundary density and its effects on anodic polarization in Ni-infiltrated Ni/YSZ SOFC snodes
Files
Accepted manuscript
Date
2021-11-15
Authors
Rix, Jillian
Mo, Boshan
Nikiforov, Alexey
Pal, Uday
Gopalan, Srikanth
Basu, Soumendra N.
Version
Accepted manuscript
OA Version
Citation
J. Rix, B. Mo, A. Nikiforov, U. Pal, S. Gopalan, S. Basu. 2021. "Quantifying Percolated Triple Phase Boundary Density and Its
Effects on Anodic Polarization in Ni-Infiltrated Ni/YSZ SOFC Anodes" Journal of Electrochemical Society, Volume 168, pp.114507-1145013. https://doi.org/10.1149/1945-7111/ac3599
Abstract
Increasing the density of percolated triple phase boundaries (TPBs) by infiltrating nanoscale electrocatalysts can improve the
performance of solid oxide fuel cell (SOFC) anodes. However, the complex microstructure of these infiltrated nanocatalysts creates
challenges in quantifying their role in anode performance improvements. In this research, scanning electron microscopy of
fractured cross-sections of a Ni-nanocatalyst infiltrated anodic symmetric cell along with three-dimensional (3-D) reconstruction of
the same anode have been used to quantify the changes in percolated TPB densities due to infiltration. This change in percolated
TPB density has been compared to the improvement in anode activation polarization resistance measured by electrochemical
impedance spectroscopy (EIS). It was found that increased TPB densities only partially accounted for the measured performance
improvement. Distribution of relaxation times (DRT) analyses showed that a reduction in the time constants of the catalytic
processes in the anode also play a role, suggesting that the added nanoscale percolated TPB boundaries are more electrochemically active as compared to the cermet TPB boundaries.