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arXiv · 2509.16515

Prediction of Li3Fe8B8 compound with rapid one-dimensional ion diffusion channels

Abstract

Using a computational crystal structure search in the Li-Fe-B ternary system, we predict a stable phase of Li3Fe8B8, featuring 1D channels that enable rapid Li-ion transport. Ab initio molecular dynamics simulations show that the Li-ion diffusion coefficient in Li3Fe8B8 surpasses that of common electrode and conductive additive materials by several orders of magnitude. The high diffusion in Li3Fe8B8 can be explained by the Frenkel-Kontorova model, which describes an incommensurate state between the Li diffusion chain and the periodic potential field caused by the FeB backbone structure. The favorable lithium-ion diffusivity and mechanical properties of Li3Fe8B8 make it a promising conductive additive for battery materials. Its itinerant ferromagnetism also offers a platform for exploring correlated-electron magnetism and spin-dependent phenomena.

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BibTeXRIS

Shiya Chen, Paul Oftedahl, Zhen Zhang, Zepeng Wu, Junjie Jiang, Vladimir Antropov, Julia V. Zaikina, Shunqing Wu, Kai-Ming Ho, Yang Sun. 2025-09-20. Prediction of Li3Fe8B8 compound with rapid one-dimensional ion diffusion channels. https://doi.org/10.1103/37v2-qt21

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