Center for Molecular Modeling - A.I. Bhatti

Crystallographic control of hydrogen ingress in bcc-iron: Insights from ab initio simulations

lmeier — Tue, 06 Jan 2026 15:07:27 +0000

L. Meier, A.I. Bhatti, L. A. I. Kestens, S. Cottenier

International Journal of Hydrogen Energy

201, 152840

2026

Abstract

Hydrogen uptake into body-centered cubic (bcc) iron as a root cause for subsequent hydrogen embrittlement, is initiated at the surface. In this paper, we quantify how readily H diffuses from the surface into the bulk. We consider a set of 10 different Fe surfaces and treat H-permeation as a two-step process. First, density-functional calculations determine the adsorption energy of an isolated H atom at every crystallographically distinct surface site. Second, for each adsorption site we map the minimum-energy pathway between the surface and the lattice. Across all orientations studied, a clear trend emerges: sites that bind hydrogen most weakly are the starting point of the lowest-barrier diffusion channels into the metal interior. Thus, the least-favorable adsorption pockets act as “gateways” for subsurface penetration. This insight provides a practical design rule: minimizing exposure of such high-energy adsorption motifs should make bcc-iron components less susceptible to hydrogen uptake and the associated embrittlement.

Gold Open Access

DOI

https://doi.org/10.1016/j.ijhydene.2025.152840

Surface-to-bulk hydrogen transport in BCC iron: a computational review of adsorption and diffusion mechanisms

lmeier — Thu, 13 Mar 2025 11:00:35 +0000

L. Meier, A.I. Bhatti, S. Cottenier

Critical Reviews in Solid State and Materials Sciences

2024

Abstract

Hydrogen embrittlement poses a significant challenge in various engineering applications. In this context, the iron/hydrogen system serves as a crucial prototype for examining the interaction between hydrogen and steel. Despite the critical importance of this topic, there is a notable lack of knowledge regarding the influence of surface characteristics on the penetration of hydrogen into materials. To address this gap, we have conducted an extensive review of the existing literature, particularly focusing on how different surface orientations of body-centered cubic (bcc) iron affect the adsorption, diffusion, and subsequent penetration of hydrogen into an iron crystal. The review primarily focuses on computational methods, incorporating experimental data for comparative analysis wherever feasible. This comprehensive synthesis of scattered information leads to several key conclusions. First, there is a systematic relationship between surface geometry and adsorption energy that has previously been overlooked. Second, bulk diffusion characteristics are recovered just a few atomic layers beneath the surface, emphasizing the importance of the initial surface layers in determining initial penetration. Third, penetrating through the surface layers is generally more challenging than further diffusion through bulk iron, with the specifics heavily dependent on the surface orientation. Studies on high-index surfaces are limited. We identify this as an area needing further research, and this review provides a solid foundation for such studies.

This work has been performed as part of the NOHENTRY project, funded by the Energy Transition Fund (Energietransitiefonds) of the Directorate-General Energy (Algemene Directie Energie) of the Federal Public Service for the Economy (FOD Economie) of Belgium. S.C. acknowledges financial support from OCAS NV by an OCAS-endowed chair at Ghent University. The computational resources and services used in this work were provided by the VSC (Flemish Supercomputer Center), funded by the Research Foundation - Flanders (FWO) and the Flemish Government - department EWI.

Gold Open Access

DOI

https://doi.org/10.1080/10408436.2024.2416435

Hydrogen Diffusion through iron surfaces

lmeier — Mon, 26 Jan 2026 13:20:21 +0000

L. Meier, A.I. Bhatti, S. Cottenier

ISBN/ISSN:

Poster

Conference / event / venue

FEARS: Faculty of Engineering and Architecture Research Symposium

Ghent, Belgium

Thursday, 26 October, 2023

Crystallographic Control of Hydrogen Ingress in BCC-Iron: Insights from Ab-Initio Simulations

lmeier — Tue, 03 Jun 2025 15:07:00 +0000

L. Meier, A.I. Bhatti, S. Cottenier

ISBN/ISSN:

Talk

Conference / event / venue

1st Conference on Hydrogen in Materials Science and Engineering (H2MSE)

Siegburg (DE)

Tuesday, 11 February, 2025 to Thursday, 13 February, 2025

Crystallographic Control of Hydrogen Ingress in BCC-Iron: Insights from Ab-Initio Simulations

lmeier — Tue, 03 Jun 2025 15:05:02 +0000

L. Meier, A.I. Bhatti, L. Kestens, S. Cottenier

ISBN/ISSN:

Poster

Conference / event / venue

ASTM Conference on Hydrogen in Materials

La Rochelle (Fr)

Tuesday, 3 June, 2025 to Friday, 6 June, 2025

Asif Iqbal Bhatti

mieke — Fri, 25 Feb 2022 08:47:17 +0000