A Physically Grounded Descriptor Decoupling Intrinsic and External Contributions to CO₂ Electroreduction over...

Area of Science:

• Catalysis
• Materials Science
• Electrochemistry

Background:

• Rational catalyst design relies on descriptors linking microscopic structure to macroscopic performance.
• Existing descriptors often neglect dynamic effects under working conditions, limiting predictive accuracy for electrocatalytic reactions.

Purpose of the Study:

• To propose a physically grounded descriptor for potential-dependent electrocatalytic performance of single-atom catalysts (SACs) in CO2 reduction.
• To decouple and quantify contributions of static electronic structure and dynamic potential response to reaction thermodynamics and kinetics.

Main Methods:

• Developed a descriptor integrating static electronic structure and dynamic response to applied potential.
• Integrated the descriptor into a microkinetic framework.
• Validated predictions against experimental measurements across various SACs and potentials.

Main Results:

• Established a direct connection between accessible parameters and emergent catalytic behavior for SACs.
• Demonstrated excellent agreement between descriptor predictions and experimental data.
• Quantified catalyst- and potential-dependent roles of intrinsic/external effects, selectivity trends, and active site restructuring.

Conclusions:

• The descriptor accurately predicts CO2 reduction performance of SACs under operating conditions.
• Provides mechanistic insights into activity, selectivity, and stability trade-offs.
• Offers fundamental principles for designing efficient SACs for CO2 electroreduction.