Electrocatalysis in Solid Oxide Fuel Cells and Electrolyzers.

Area of Science:

• Electrochemistry
• Materials Science
• Energy Conversion

Background:

• Solid oxide electrochemical cells (SOCs) are key for energy-to-X and X-to-energy technologies, including green hydrogen and ammonia.
• High operating temperatures (400-900 °C) in SOCs enable efficient thermodynamics and kinetics for electrochemical conversion and storage.
• Current electrocatalytic materials in SOCs limit reversible operation and fuel flexibility.

Purpose of the Study:

• To review electrocatalytic materials for oxygen-ion-conducting SOCs (O-SOCs) and proton-conducting SOCs (H-SOCs).
• To analyze material composition and structure effects on electrochemical activity and catalytic performance.
• To identify bottlenecks in catalyst deactivation and propose guidelines for designing improved SOC catalysts.

Main Methods:

• Literature review of electrocatalytic materials in SOCs.
• Analysis of electrochemical activity across various reactions based on material properties.
• Discussion of catalyst deactivation mechanisms under different operating conditions.

Main Results:

• Diverse electrocatalytic materials are used in O-SOCs and H-SOCs, with varying performance linked to composition and structure.
• Catalyst deactivation is a significant bottleneck affecting long-term SOC performance.
• Optimal catalytic performance depends on specific electrochemical reactions and operating conditions.

Conclusions:

• Electrocatalyst development is crucial for enhancing the fuel flexibility and reversible operation of SOCs.
• Guidelines are provided for evaluating catalyst performance and designing next-generation SOC electrode materials.
• Further research into catalyst design can unlock the full potential of SOCs for energy conversion and storage.