Highly Active and Redox-Stable Ce-Doped LaSrCrFeO-Based Cathode Catalyst for CO2 SOECs

Area of Science:

• Materials Science
• Electrochemistry
• Catalysis

Background:

• Lanthanum chromate-based perovskites are promising cathode materials for high-temperature CO2 electrolysis due to redox stability.
• Limitations include suboptimal catalytic activity and insufficient CO2 adsorption, hindering overall cell performance and Faraday efficiency.

Purpose of the Study:

• To enhance the electrochemical performance of La0.7Sr0.3Cr0.5Fe0.5O3-δ (LSCrF) by doping with cerium (Ce).
• To investigate the role of Ce doping in promoting catalytic activity, CO2 adsorption, and oxygen vacancy formation for improved CO2 electrolysis.

Main Methods:

• Cerium (Ce) was doped into the A-site of La0.7Sr0.3Cr0.5Fe0.5O3-δ (LSCrF) perovskite oxide.
• Electrochemical performance and CO2 electrolysis were evaluated for Ce-doped and undoped LSCrF cathodes.
• In situ characterization under operational conditions was used to analyze structural changes and oxygen vacancy formation.

Main Results:

• Ce doping successfully introduced oxygen vacancies into the LSCrF lattice after reduction.
• Increased oxygen vacancies facilitated oxygen ion mobility and enhanced CO2 chemical adsorption.
• Ce-doped LSCrF cathodes exhibited superior electrochemical performance and higher Faraday efficiencies in CO2 electrolysis compared to undoped LSCrF.

Conclusions:

• Cerium doping is an effective strategy to improve the performance of lanthanum chromate-based perovskite cathodes for CO2 electrolysis.
• The enhanced performance is attributed to increased oxygen vacancies, improved catalytic activity, and better CO2 adsorption.
• Ce-doped LSCrF presents a promising functional material for efficient high-temperature CO2 electrolysis applications.