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DOE OSTI · 3383045

Group-Additivity–Embedded Multiscale Modeling for Electric Field-Enhanced Nanocatalysis

Abstract

Elucidating structure-performance relationships remains a central challenge in field-enhanced catalysis, where nanoparticles exhibit nonuniform surface sites with site-dependent responses to electric fields. Low-coordination sites (edges, corners, and tips) are particularly electric field-sensitive (EF), leading to nonuniform charge distribution, adsorption energies, and catalytic activity. Here, using ammonia decomposition on a ruthenium cluster as a model system, we develop a transferable multiscale framework integrating density functional theory, group additivity (GA), Brønsted-Evans-Polanyi scaling, and microkinetic modeling to predict EF-dependent activity across nonuniform cluster sites. Across sites and fields, the nitrogen adsorption energy (E N ) emerges as the governing descriptor, yielding robust volcano relationships whose optimum shifts systematically with field: negative fields strengthen N binding via electron accumulation, while positive fields weaken N binding via charge depletion, moving the optimal E N toward weaker binding. Microkinetic analysis shows that N≡N bond formation remains the key kinetic bottleneck over most conditions; positive fields lower the effective barrier and, critically, increase the fraction of near-optimal active sites, leading to a net enhancement in overall activity relative to zero-field and negative-field cases. By capturing EF- and site-dependent energetics with high accuracy and low computational cost, this GA-embedded multi-scale simulation workflow provides a physically interpretable route to predict and design field-enhanced nanocatalysis.

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BibTeXRIS

Li, Qiang [Univ. of Massachusetts, Lowell, MA (United States)] (ORCID:0000000155682334), Liu, Yilang [Univ. of Massachusetts, Lowell, MA (United States)], Zhao, Runze [Worcester Polytechnic Institute, MA (United States)], Che, Fanglin [Univ. of Massachusetts, Lowell, MA (United States); Worcester Polytechnic Institute, MA (United States)] (ORCID:0000000151098296). 2026-07-02. Group-Additivity–Embedded Multiscale Modeling for Electric Field-Enhanced Nanocatalysis. https://doi.org/10.1021/acscatal.6c01038

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