2025 AIChE Annual Meeting

(677a) Group Additivity-Driven Model for Field-Enhanced Catalysis

Authors

Qiang Li - Presenter, University of Massachusetts Lowell
Runze Zhao, University of Massachusetts Lowell
Yilang Liu, University of Massachusetts Lowell
Fanglin Che, University of Massachusetts Lowell
Applying an external electric field can rearrange the molecular orbitals and tune the energetics of the polarized species (e.g., NHx) over catalysts and overcome the kinetic limitation at low temperature [1]. Importantly, metal catalyst clusters feature diverse exposed sites that respond differently to external fields based on their structural characteristics, leading to variations in catalytic activity. Machine learning (ML) offers a powerful tool for rapidly screening structure–performance relationships in this context. Here, we use NH₃ decomposition over a Ru₄₅ cluster as a model system to investigate how nanocluster sites influence catalytic performance under electric fields—an essential step toward advancing field-enhanced catalysis.

By combining multi-scale simulation (DFT, microkinetic modeling) with ML, we built a high-quality species-cluster interaction database and developed a physics-informed ML method using active site coordination number (CN) and the group additivity (GA) framework [3] (Figure 1a) to predict correlations among field-dependent catalytic activity and cluster sites. Our results (Figure 1b–c) show that the CN-GA efficiently screens species-catalyst interactions across diverse environments, accurately predicting species adsorptions for intermediates. Figure 1d shows surface charge redistribution as the field shifts from –1 to 1 V/Å, with edge and tip sites exhibiting heightened sensitivity. Notably, electron accumulation at edge sites enhances nitrogen adsorption (Figure 1e), underscoring the role of electrostatics in modulating species-site interactions and catalytic reactions. Our CN-GA model accurately predicts the system’s dipole moment and polarizability, enabling precise estimation of field-dependent energetics. These ML-predicted energetics are then integrated into a microkinetic model to reveal how nanocluster sites impact catalytic performance under fields, ultimately providing design principles for optimizing catalyst structures in field-enhanced catalysis.

References

  1. Zhao, R,. Li, Q., Zhu C., Che. F. JACS Au, 5, 3, 1121–1132 (2025).
  2. Q.; Wittreich, G. Vlachos, D. G. ACS Sustainable Chem. Eng.9, 3043–3049 (2021).