Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
7996910 | Journal of Alloys and Compounds | 2016 | 28 Pages |
Abstract
Ultra-fine Gd-doped ceria (GDC) powders were synthesized via co-precipitation using ammonium carbonate as the precipitant. The crystallite size of the resultant GDC powders was measured as â¼33 nm. The dilatometry test of the powder compacts and the relative density measurement of sintered pellets with various sintering temperatures revealed the synthesized nano-GDC powders had superior sinterability compared to commercial GDC powders (e.g., 96% vs 78% in relative density at 1300 °C, respectively). Based on the total conductivity measurement of the co-precipitated GDC via electrochemical impedance spectroscopy, we found there was an optimum sintering temperature range (1300-1400 °C) to achieve both high density and high conductivity due to significant increase in grain boundary resistance at higher temperature (1500 °C). Moreover, the nano-sized and highly sinterable co-precipitated GDC effectively enhanced oxygen reduction reaction at the La0.6Sr0.4Co0.2Fe0.8O3âδ/GDC composite cathode due to increase in active reaction sites as well as enhanced phase connectivity in 3D-bulk at lower sintering temperatures.
Related Topics
Physical Sciences and Engineering
Materials Science
Metals and Alloys
Authors
Dong Woo Joh, Manasa K. Rath, Jin Wan Park, Jeong Hwa Park, Ki Hyun Cho, Seunghwan Lee, Kyung Joong Yoon, Jong-Ho Lee, Kang Taek Lee,