Atomistic Models of Long-Term Hydrogen Diffusion in Metals

M.P. Ariza; K.G. Wang; M. Ortiz

doi:10.4028/www.scientific.net/AST.93.118

Paper Titles

Optimization of Hydrogen Production by Co-Culture of Clostridium beijerinckii and Rhodobacter sphaeroides Bacteria
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Plasma Chemical Reactor for Hydrogen Production
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Activated Carbon Fibre Monoliths for Hydrogen Storage
p.102

Hydrogenation of Nanocrystalline Mg₂Ni Alloy Prepared by High Energy Ball-Milling Followed by Equal-Channel Angular Pressing or Cold Rolling
p.112

Atomistic Models of Long-Term Hydrogen Diffusion in Metals
p.118

Hydrogen Technologies and Applications: Safety
p.124

A Millimeter Scale Reactor Integrated PEM Fuel Cell Energy System with an On-Board Hydrogen Production, Storage and Regulation Unit for Autonomous Small Scale Applications
p.131

Study of New Active Materials for Rechargeable Sodium-Ion Batteries
p.137

Relating Electrochemistry of New Organic Materials for Batteries and Fundamental Understanding through DFT Calculations
p.146

HomeAdvances in Science and TechnologyAdvances in Science and Technology Vol. 93Atomistic Models of Long-Term Hydrogen Diffusion...

Atomistic Models of Long-Term Hydrogen Diffusion in Metals

Abstract:

The effective and efficient storage of hydrogen is one of the key challenges in developing a hydrogen economy. Recently, intensive research has been focused on developing and optimizing metal-based nanomaterials for high-speed, high-capacity, reversible hydrogen storage applications. Notably, the absorption and desorption of hydrogen in nanomaterials is characterized by an atomic, deformation-diffusion coupled process with a time scale of the order of seconds to hours--far beyond the time windows of existing simulation technologies such as Molecular Dynamics (MD) and Monte Carlo (MC) methods. In this work, we present a novel deformation-diffusion coupled computational framework, which allows the long-term simulation of such slow processes and at the same time maintains a strictly atomistic description of the material. Specifically, we first propose a theory of non-equilibrium statistical thermodynamics for multi-species particulate solids based on Jayne's maximum entropy principle and the meanfield approximation approach. This non-equilibrium statistical thermodynamics model is then coupled with novel discrete kinetics laws, which governs the diffusion of mass--and possibly also conduction of heat--at atomic scale. Finally, this thermo-chemo-mechanical coupled system is solved numerically using a staggered procedure. The salient features of this computational framework are demonstrated in the simulation of a specific hydrogen diffusion problem using palladium nanofilms, which comes with a simulation time of one second. More generally, the proposed computational framework can be considered as an ideal tool for the study of many deformation-diffusion coupled phenomena in hydrogen-storage-related applications including, but not limited to, hydrogen embrittlement, grain boundary diffusion, and various cyclic behaviors.