Reactive force field simulation of proton diffusion in BaZrO3 using an empirical valence bond approach
MetadataShow full item record
Copyright © 2011 IOP Institute of Physics
A new reactive force field to describe proton diffusion within the solid-oxide fuel cell material BaZrO3 has been derived. Using a quantum mechanical potential energy surface, the parameters of an interatomic potential model to describe hydroxyl groups within both pure and yttrium-doped BaZrO3 have been determined. Reactivity is then incorporated through the use of the empirical valence bond model. Molecular dynamics simulations (EVB-MD) have been performed to explore the diffusion of hydrogen using a stochastic thermostat and barostat whose equations are extended to the isostress-isothermal ensemble. In the low concentration limit, the presence of yttrium is found not to significantly influence the diffusivity of hydrogen, despite the proton having a longer residence time at oxygen adjacent to the dopant. This lack of in influence is due to the fact that trapping occurs infrequently, even when the proton diffuses through octahedra adjacent to the dopant. The activation energy for diffusion is found to be 0.42 eV, in good agreement with experimental values, though the prefactor is slightly underestimated.
Showing items related by title, author, creator and subject.
Proton dynamics in phosphotungstic acid impregnated mesoporous silica proton exchange membrane materialsLamb, K.; Mole, R.; Yu, D.; De Marco, Roland; Bartlett, J.; Windsor, S.; Jiang, San Ping; Zhang, J.; Peterson, V. (2017)Phosphotungstic acid is an excellent proton conductor that can be incorporated into porous supports, and nanocomposite proton exchange membrane materials made from mesoporous silica impregnated with phosphotungstic acid ...
Potentiometric Investigation of Protonation Reactions at Aqueous-Aqueous Boundaries within a Dual-Stream Microfluidic StructureStrutwolf, J.; Collins, C.; Adamiak, W.; Arrigan, Damien (2010)The laminar flow regime prevailing in pressure-driven flow through a Y-shaped microfluidic channel was utilized to create a stable boundary between two aqueous liquids. Transverse transport of ions between these two liquids ...
Amino-functionalized mesoporous silica based polyethersulfone-polyvinylpyrrolidone composite membranes for elevated temperature proton exchange membrane fuel cellsZhang, Jin; Lu, S.; Zhu, H.; Chen, Kongfa; Xiang, Y.; Liu, Jian; Forsyth, M.; Jiang, San Ping (2016)It is important to find alternative membranes to the state-of-the-art polybenzimidazole based high temperature proton exchange membranes with high proton conductivity at elevated temperature but with simple synthesis ...