First‐Principles Active‐Site Model Design for High‐Entropy‐Alloy Catalyst Screening: The Impact of Host Element Selection on Catalytic Properties

Abstract Active‐site models comprise miniature active sites on the host element, providing one of effective descriptors for screening high‐entropy‐alloy (HEA) catalysts using machine learning. This study investigates the impact of host elements on the electronic properties of active sites via density functional theory (DFT), where the active‐site model is used in the HEA electrocatalysts. Also, the appropriate host element selection significantly affects the system's surface structures, electronic, and catalytic properties that adsorbate adsorption energy, d‐band center, Bader charge, Zero‐point energy, and entropy are used as accuracy verification parameters compared to the original surface. Ultimately, the novel guideline for active‐site model construction is proposed using the simple example of PtPdFeCoNi high‐entropy alloys. This investigation demonstrates that the host element selection is a crucial parameter to the active‐site models, influencing the electronic structure and electrocatalytic properties.