Tuning the Thickness of Ba-Containing "Functional" Layer toward High-Performance Ceria-Based Solid Oxide Fuel Cells

Area of Science:

• Materials Science
• Electrochemistry
• Energy Conversion

Background:

• Commercialization of ceria-based solid oxide fuel cells (SOFCs) is hindered by challenges in achieving high efficiency and power density.
• Developing advanced anode architectures is crucial for improving SOFC performance at reduced operating temperatures.

Purpose of the Study:

• To design and investigate a novel bilayered anode structure for ceria-based SOFCs.
• To understand the role of a functional Ni-BaZr0.1Ce0.7Y0.2O3-δ (Ni-BZCY) layer in forming an in situ electron-blocking layer.
• To optimize the Ni-BZCY layer thickness for enhanced electrochemical performance.

Main Methods:

• Fabrication of a Ce0.8Sm0.2O2-δ (SDC)-based SOFC with a bilayered anode comprising Ni-SDC and Ni-BZCY.
• In situ formation of an electron-blocking layer at the anode/electrolyte interface during sintering.
• Electrochemical characterization to evaluate open circuit voltage (OCV) and power density.

Main Results:

• The Ni-BZCY functional layer successfully generated an in situ electron-blocking layer.
• The thickness of the Ni-BZCY layer critically impacted the electron-blocking layer quality and cell performance.
• A cell with a 50 μm Ni-BZCY layer achieved a peak power density of 1068 mW cm⁻² at 650 °C and a high open circuit voltage.

Conclusions:

• The developed bilayered anode structure significantly improves the performance of ceria-based SOFCs.
• The in situ generated electron-blocking layer is key to achieving high power density and efficiency.
• This optimized SOFC design shows promise for efficient energy conversion at reduced temperatures.