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Hyun Gyu Park

Publications and source records attributed to Hyun Gyu Park.

2 recordsLinked to original sources

Accelerated Discovery of Nitrogen-Coordinated Dual-Atom Hydrogen Evolution Reaction Electrocatalysts via Machine Learning Potentials

The hydrogen evolution reaction (HER) is central to sustainable hydrogen production, and nitrogen coordinated dual atom catalysts (DACs) offer a promising route to noble metal activity at low cost. Yet their vast compositional and coordination design space remains underexplored, as density functional theory (DFT) screening at scale is prohibitive. Here, we map the HER landscape of graphene supported TM2@Nx-Gr DACs, screening 23 transition metals across 20 nitrogen coordination motifs using a machine learning potential (MLP) benchmarked against DFT. Intermediate coordination (2N to 4N) consistently yields near-optimal ΔGH*, with Ti2@2Na, Mn2@2Na, Fe2@2Na, Cu2@2Na, Rh2@2Na, Zr2@2Na, Zr2@2Nb, Zr2@2Nc, Nb2@2Nc, Zr2@2Nd, Mn2@2Ne, Mn2@2Nf, Ti2@3Na, Au2@3Na, Fe2@3Na, Pd2@3Nb, Rh2@3Nc, Rh2@3Nd, Au2@3Nd, V2@4Na, Ti2@4Nb, Pd2@4Nb, Ti2@4Nc, Cr2@4Nd, Ni2@4Nd, Cu2@4Nd emerging as standout, synthesizable candidates, most exhibiting metallic or narrow gap (<0.25 eV) character. The MLP reaches near-DFT accuracy, with a mean absolute error of 80 meV for Gibbs binding free energies at orders of magnitude lower computational cost, establishing MLP driven screening as a practical engine for next-generation catalyst discovery.

cond-mat.mtrl-sci↗

A Bayesian Committee Machine Potential for Organic Nitrogen Compounds

Large-scale computer simulations of chemical atoms are used in a wide range of applications, including batteries, drugs, and more. However, there is a problem with efficiency as it takes a long time due to the large amount of calculation. To solve these problems, machine learning interatomic potential (ML-IAP) technology is attracting attention as an alternative. ML-IAP not only has high accuracy by faithfully expressing the density functional theory (DFT), but also has the advantage of low computational cost. However, there is a problem that the potential energy changes significantly depending on the environment of each atom, and expansion to a wide range of compounds within a single model is still difficult to build in the case of a kernel-based model. To solve this problem, we would like to develop a universal ML-IAP using this active Bayesian Committee Machine (BCM) potential methodology for carbon-nitrogen-hydrogen (CNH) with various compositions. ML models are trained and generated through first-principles calculations and molecular dynamics simulations for molecules with only CNH. Using long amine structures to test an ML model trained only with short chains, the results show excellent consistency with DFT calculations. Consequently, machine learning-based models for organic molecules not only demonstrate the ability to accurately describe various physical properties but also hold promise for investigating a broad spectrum of diverse materials systems.

cond-mat.mtrl-sci↗