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arXiv · 2610.02905

Preparation sequence controls oxygen partitioning between boron and lithium on tungsten

Predrag S Krstic·Meral Sharkass·Swarit Dwivedi·Dalia Sayed Ahmed·Yun Kyung Shin·Adri CT van Duin
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Abstract

Classical reactive molecular dynamics of boron- and lithium-conditioned tungsten surfaces show that the order in which boron and oxygen are introduced - not the boron inventory - controls surface chemistry. On a thin engineered tungsten oxide, boron captures 81% of oxygen and consumes the oxide; on an engineered ~2 nm mixed WO3/WO2 film, boron captures only 20% and leaves 52% of reaction-zone tungsten in WO3-like coordination; and in a co-deposited W-B substrate later exposed to oxygen, boron captures only 28% despite a tenfold larger inventory. Adding lithium leaves the oxide-first cases unchanged but transforms the co-deposited case, where lithium becomes the dominant oxygen captor (58%) and a lithium-borate-glass-like network form. We outline the expected, divergent responses of the boron-only and boron-plus-lithium materials to deuterium irradiation.

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Predrag S Krstic, Meral Sharkass, Swarit Dwivedi, Dalia Sayed Ahmed, Yun Kyung Shin, Adri CT van Duin. 2026-10-02. Preparation sequence controls oxygen partitioning between boron and lithium on tungsten. https://arxiv.org/abs/2610.02905

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