Direct Deoxygenation of Phenol over Fe-Based Bimetallic Surfaces Using On-the-Fly Surrogate Models
Isaac Onyango1,2, Qiang Zhu1,2
1Department of Mechanical Engineering and Engineering Science, University of North Carolina at Charlotte, Charlotte, North Carolina 28223, United States.
The Journal of Physical Chemistry. C, Nanomaterials and Interfaces
|October 29, 2025
Summary
We developed a faster computational method for studying phenol direct deoxygenation (DDO) on iron-based catalysts. Subsurface cobalt and nickel improve catalytic performance, while top-layer additions hinder the deoxygenation process.
Area of Science:
- Surface science
- Computational chemistry
- Catalysis
Background:
- Phenol direct deoxygenation (DDO) is crucial for removing oxygenated compounds.
- Developing efficient catalysts for DDO requires understanding reaction mechanisms on metal surfaces.
- Computational methods are essential for exploring complex surface reactions.
Purpose of the Study:
- To investigate the direct deoxygenation (DDO) mechanism of phenol on Fe-based bimetallic surfaces.
- To evaluate the performance of a new Gaussian process regression (GPR) accelerated calculator for surface reaction studies.
- To provide insights into designing effective bimetallic catalysts for selective deoxygenation.
Main Methods:
- Accelerated nudged elastic band (NEB) calculations using a Gaussian process regression (GPR) calculator.
- Systematic examination of DDO on pure Fe(110) and surfaces modified with Co and Ni (top and subsurface).
- Comparison of GPR-NEB accuracy and speed against conventional density functional theory (DFT) calculations.
Main Results:
- The GPR calculator achieved up to 3x speedup with energy barrier errors below 0.015 eV.
- Subsurface Co and Ni substitutions maintained favorable thermodynamics and kinetics for DDO.
- Top-layer Co and Ni substitutions increased C-O bond cleavage barriers and made the reaction unfavorable.
Conclusions:
- GPR-accelerated transition state searches are effective for complex surface reactions.
- Subsurface alloying with Co and Ni shows promise for enhancing Fe-based catalysts for phenol DDO.
- Top-layer alloying is detrimental to the DDO process on these Fe-based surfaces.
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