Copper-Enhanced CO₂ Electroreduction in SOECs.

Area of Science:

• Materials Science
• Electrochemistry
• Catalysis

Background:

• Cobalt (Co)- and nickel (Ni)-free electrocatalysts are crucial for commercializing solid-oxide electrolysis cells (CO2-SOECs) due to projected critical demand for these metals by 2050.
• Current CO2-SOEC electrodes face challenges like structural degradation and carbon deposition, particularly at high overpotentials.

Purpose of the Study:

• To design and synthesize a novel, multipurpose electrode material for CO2-SOECs that avoids the use of cobalt and nickel.
• To evaluate the potential of a copper-substituted perovskite oxide as a viable alternative for both anode and cathode applications in CO2-SOECs.

Main Methods:

• La0.6Sr0.4Fe0.8Cu0.2O3-δ (LSFCu) was synthesized using the solution combustion method.
• Material characterization included X-ray powder diffraction with Rietveld refinement, X-ray photoelectron spectroscopy, thermogravimetric analyses, and electrical conductivity assessment.
• Electrochemical performance was evaluated in CO2 electrolysis, including area-specific resistance measurements and testing in a symmetric CO2-SOEC at 850 °C.

Main Results:

• The synthesized LSFCu material demonstrated structural stability and favorable electrical conductivity.
• LSFCu exhibited promising performance as both an anode and cathode material for CO2 electrolysis.
• A symmetric LSFCu-based CO2-SOEC achieved a remarkable current density of 1.22 A/cm² at 1.5 V and 850 °C.

Conclusions:

• Copper substitution in La0.6Sr0.4FeO3-δ offers a promising pathway to develop cobalt- and nickel-free electrodes for CO2-SOECs.
• The developed LSFCu material shows potential as a multipurpose electrode, addressing limitations of current CO2-SOEC technologies.
• This work presents a proof of concept for a high-performance, symmetric CO2-SOEC utilizing a novel, earth-abundant catalyst.