Lanthanum Ferrites-Based Exsolved Perovskites as Fuel-Flexible Anode for Solid Oxide Fuel Cells

Area of Science:

• Materials Science
• Electrochemistry
• Catalysis

Background:

• Lanthanum ferrite perovskites are explored as potential electrocatalysts for solid oxide fuel cells (SOFCs).
• Developing efficient and durable anode materials is crucial for direct dry fuel oxidation in SOFCs.

Purpose of the Study:

• To synthesize exsolved perovskites from nickel-doped lanthanum ferrites for SOFC anode applications.
• To evaluate the catalytic performance, conductivity, durability, and fuel flexibility of the novel electrocatalyst.

Main Methods:

• Nickel doping of lanthanum ferrite (La_0.6Sr_0.4Fe_0.8Co_0.2O₃) via incipient wetness.
• Thermal treatments including calcination in air and reduction in diluted hydrogen to induce exsolution.
• Characterization of the resulting two-phase material (Ruddlesden-Popper structure and α-Fe_100-y-zCo_yNi_zO_x).

Main Results:

• Successful synthesis of a two-phase material with exsolved nickel-containing oxide nanoparticles.
• The electrocatalyst exhibits excellent electronic conductivity under reducing conditions.
• Outstanding catalytic activity for direct oxidation of H₂, methane, syngas, methanol, glycerol, and propane.
• Demonstrated durability and tolerance to sulfur poisoning.

Conclusions:

• Exsolved perovskites derived from Ni-doped lanthanum ferrites are highly effective anode electrocatalysts for SOFCs.
• The material's properties enable efficient direct oxidation of a wide range of dry fuels.
• Potential for integration into various SOFC configurations, including as a pre-layer for conventional anodes.