A high-performance cathode for the next generation of solid-oxide fuel cells.

Area of Science:

• Materials Science
• Electrochemistry
• Energy Conversion

Background:

• Solid-oxide fuel cells (SOFCs) offer efficient and environmentally friendly power generation with fuel flexibility.
• High operating temperatures (800–1,000°C) for traditional SOFCs lead to high costs and material limitations.
• Developing intermediate-temperature (500–700°C) SOFCs is crucial for wider adoption, but requires improved cathode materials.

Purpose of the Study:

• To introduce a novel cathode material, Ba(0.5)Sr(0.5)Co(0.8)Fe(0.2)O(3-delta) (BSCF), for reduced-temperature SOFC operation.
• To evaluate the performance of BSCF in thin-film doped ceria fuel cells at intermediate temperatures.
• To assess the suitability of BSCF for single-chamber fuel cell configurations.

Main Methods:

• BSCF was synthesized and incorporated as a cathode material in a thin-film doped ceria fuel cell.
• Electrochemical performance was measured using humidified hydrogen as fuel and air as the cathode gas at 600°C and 500°C.
• Oxygen diffusion rates through the BSCF material were investigated to understand performance.

Main Results:

• BSCF-based fuel cells achieved high power densities of 1,010 mW cm⁻² at 600°C and 402 mW cm⁻² at 500°C.
• The material demonstrated excellent performance in single-chamber fuel cell operation.
• High oxygen diffusion rates through BSCF were identified as the reason for its high power output.

Conclusions:

• BSCF is a promising cathode material for intermediate-temperature SOFCs, overcoming limitations of traditional materials.
• The material's high performance and suitability for single-chamber operation pave the way for practical SOFC implementation.
• Reduced operating temperatures enabled by BSCF can significantly lower SOFC costs and broaden their applicability.