A Highly Efficient and Robust Perovskite Anode with Iron-Palladium Co-exsolutions for Intermediate-Temperature...

Area of Science:

• Materials Science
• Electrochemistry
• Energy Conversion

Background:

• Perovskite anodes in intermediate-temperature solid-oxide fuel cells (IT-SOFCs) suffer from low performance and insufficient catalytic activity.
• Developing advanced anode materials is crucial for improving IT-SOFC efficiency and applicability.

Purpose of the Study:

• To develop a novel perovskite anode material with enhanced catalytic activity and electrochemical performance for IT-SOFCs.
• To investigate the effect of Fe-Pd co-exsolutions on the anode's properties and performance.

Main Methods:

• Synthesis of a novel perovskite material: La_0.8 Sr_0.2 Fe_0.9 Nb_0.1 Pd_0.04 O_3-δ (LSFNP).
• Characterization of exsolved Fe⁰ and Pd⁰ nanoparticles on the perovskite surface under hydrogen atmosphere.
• Electrochemical testing of single cells using the LSFNP anode in IT-SOFCs.

Main Results:

• Fe-Pd metallic nanoparticles were successfully exsolved on the LSFNP anode surface during operation.
• Pd exsolutions significantly enhanced H₂ adsorption and charge transfer, improving the parent anode's (LSFN) performance.
• The LSFNP anode achieved a maximum power density of 287.6 mW/cm² at 800°C and showed excellent redox stability, coking, and sulfur tolerance.
• Performance enhancement was particularly notable at lower temperatures and H₂ concentrations, with a power density ratio of LSFNP/LSFN reaching 18 at 650°C with 5% H₂.

Conclusions:

• Pd exsolution is a reliable strategy to create high-performance, stable anode materials for IT-SOFCs.
• The developed Pd-decorated LSFNP anode demonstrates superior electrochemical performance and durability compared to the parent material.
• This approach effectively addresses the limitations of perovskite anodes in IT-SOFC applications.