Low-dimensional carbon nanomaterials such as fullerenes, nanotubes, graphene and diamondoids have extraordinary physical and chemical properties1, 2. Compression-induced polymerization of aromatic molecules could provide a viable synthetic route to ordered carbon nanomaterials3, 4, but despite almost a century of study5, 6, 7, 8, 9 this approach has produced only amorphous products10, 11, 12, 13, 14. Here we report recovery to ambient pressure of macroscopic quantities of a crystalline one- dimensional sp3 carbon nanomaterial formed by high-pressure solid-state reaction of benzene. X-ray and neutron diffraction, Raman spectroscopy, solid-state NMR, transmission electron microscopy and first-principles calculations reveal close- packed bundles of subnanometre-diameter sp3-bonded carbon threads capped with hydrogen, crystalline in two dimensions and short-range ordered in the third. These nanothreads promise extraordinary properties such as strength and stiffness higher than that of sp2 carbon nanotubes or conven tional high-strength polymers15. They may be the first member of a new class of ordered sp3 nanomaterials synthesized by kinetic control of high-pressure solid-state reactions.
At a glance
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- Supplementary Information (2.52 MB)