Single-Atom Catalysts: Are You Really Single?

Area of Science:

• Materials Science
• Electrochemistry
• Catalysis

Background:

• Single-atom catalysts (SACs) offer unique properties for various catalytic applications, including electrocatalysis.
• Their simple active sites make them attractive for theoretical modeling.
• Current theoretical models often overlook the influence of pH and electrode potential on SAC active sites.

Purpose of the Study:

• To highlight the necessity of evaluating the actual state of single-atom electrocatalysts under operating conditions.
• To introduce the application of surface Pourbaix diagrams for single-atom catalysts.
• To guide the development of novel electrocatalytic materials by considering environmental factors.

Main Methods:

• Reviewing recent advancements in designing Pourbaix diagrams specifically for SACs.
• Discussing the transferability of electrochemical surface Pourbaix concepts to SACs.
• Emphasizing the importance of considering the dynamic nature of active sites.

Main Results:

• Theoretical models must account for pH and potential-induced changes in SAC active sites.
• Surface Pourbaix plots provide a framework for understanding SAC stability and speciation.
• Accurate modeling of SACs requires integrating thermodynamic and electrochemical data.

Conclusions:

• The actual state of single-atom electrocatalysts under operating conditions is critical for predicting their performance.
• Surface Pourbaix diagrams are essential tools for the rational design and optimization of SACs.
• Future research should focus on developing robust theoretical frameworks that incorporate environmental influences on catalytic materials.