Theory of electrocatalysis: hydrogen evolution and more

Area of Science:

• Computational Chemistry
• Materials Science
• Electrochemistry

Background:

• Density Functional Theory (DFT) alone is inadequate for modeling electrochemical reactions due to interface size and electrode potential challenges.
• Existing methods struggle to accurately represent the complexities of electrochemical interfaces and reactions.

Purpose of the Study:

• To develop a novel theory of electrocatalysis that overcomes the limitations of DFT for electrochemical systems.
• To explain the role of metal d-bands near the Fermi level in lowering activation energy for charge transfer reactions.
• To validate the theory with experimental data for the hydrogen evolution reaction.

Main Methods:

• Integration of Density Functional Theory (DFT) with a model for electrochemical electron transfer.
• Theoretical framework to explain the influence of metal d-band electronic structure on reaction kinetics.
• Application and validation against experimental results for the hydrogen evolution reaction (HER).

Main Results:

• The combined DFT and electron transfer model successfully addresses limitations of DFT for electrochemical reactions.
• The theory elucidates the mechanism by which metal d-bands near the Fermi level facilitate charge transfer.
• Excellent agreement was achieved between theoretical predictions and experimental data for HER on various electrode types.

Conclusions:

• The developed theory provides a robust framework for understanding and predicting electrocatalytic activity.
• The method is extensible to other electrochemical reactions, with initial promising results for OH adsorption on Pt(111).
• This approach offers a significant advancement in modeling electrochemical processes and designing efficient electrocatalysts.