Nanoalloy electrocatalysis: simulating cyclic voltammetry from configurational thermodynamics with adsorbates

Area of Science:

• Computational materials science
• Surface science
• Electrocatalysis

Background:

• Nanoalloys are crucial for electrocatalysis, but understanding alloying effects on adsorption is complex.
• Cyclic voltammetry (CV) is a key technique for characterizing electrocatalytic processes.
• Predictive modeling of nanoalloy behavior is essential for catalyst design.

Purpose of the Study:

• To simulate adsorption isotherms of nanoalloys with adsorbates.
• To determine the resulting cyclic voltammetry (CV) for electrocatalysis.
• To investigate the non-linear effects of alloying on CV and guide nanoalloy design.

Main Methods:

• Hybrid-ensemble Monte Carlo simulations combined with cluster expansion.
• Extension of cluster expansion to non-exchangeable coupled lattices for nanoalloys.
• Mapping 2D CV for Palladium-Platinum (Pd-Pt) nanoalloys as a function of potential and composition.

Main Results:

• Simulated adsorption isotherms for nanoalloys with adsorbates.
• Generated 2D CV for Pd-Pt nanoalloys, demonstrating highly non-linear alloying effects.
• Correlated specific CV features with H-adsorption on multiple sites and alloy configurations.

Conclusions:

• The simulation method accurately predicts CV from nanoalloy adsorption.
• Alloying significantly and non-linearly impacts CV, offering design insights.
• This approach provides a robust framework for designing tailored nanoalloys for electrocatalysis.