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arXiv · 2609.33478

Toward catalyst-mediated growth of diamond and cubic boron nitride wires

Rodney S. Ruoff
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Abstract

A reproducible method for sustained catalyst-mediated growth of diamond and cubic boron nitride (cBN) wires has yet to be established. Catalyst-assisted growth has produced carbon and boron nitride nanotubes and a wide range of elemental, compound and alloy nanowires. Diamond and cBN wires could combine high specific stiffness and strength with heat conduction and electrical insulation. I propose vapor-liquid-solid (VLS) and vapor-solid-solid (VSS) routes in which temperature, feed, catalyst or starting contact changes between formation of the first diamond or cBN segment and its continued growth. The approaches include switching from carbide or boron-rich starter wires, depositing catalyst on selected facets of existing crystals, and using local solid feedstock to supply the catalyst during initial growth. Historical diamond-whisker reports motivate renewed tests of diamond-metal contacts. The proposed experiments ask whether these contacts can favor tetrahedral bonding while maintaining a supply of atoms to the growing wire. Both single-crystal and polycrystalline products, from nanometer to micrometer and larger diameters, are of interest.

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Rodney S. Ruoff. 2026-09-27. Toward catalyst-mediated growth of diamond and cubic boron nitride wires. https://arxiv.org/abs/2609.33478

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