LSCF powders with a specific surface area of 25.2 m2 g-1 and an average particle size of 89 nm are synthesized by the polymerizable complex method. The use of nanocrystalline LSCF powders allows the fabrication of an interlayer-free nanoporous cathode on top of an ScSZ electrolyte at a low temperature at which non-electrocatalytic secondary phases cannot form. The electrochemical performance of the interlayer-free cathode depends largely on the sintering temperature. A cathode sintered at below 750 °C lacks sufficient mechanical adhesion to the electrolyte, while the electrode surfaces are locally densified when sintered at above 800 °C. Impedance spectroscopy combined with microstructural evidence reveals that the optimum sintering temperature for LSCF is 750 °C. This avoids excess densification and grain growth, and results in the lowest polarization resistance (0.048 Ω cm2 at 750 °C).
Bibliographical noteFunding Information:
The work was the outcome of a fostering project of the Specialized Graduate School of Hydrogen and Fuel Cell supported financially by the Ministry of Commerce, Industry and Energy (MOCIE) and Seoul R&BD Program (CS070157). It was also partially supported by the Korea Science and Engineering Foundation (KOSEF) through the National Research Laboratory Program funded by the Ministry of Science and Technology (No. R0A-2005-000-10011-0).
All Science Journal Classification (ASJC) codes
- Renewable Energy, Sustainability and the Environment
- Energy Engineering and Power Technology
- Physical and Theoretical Chemistry
- Electrical and Electronic Engineering