The synthesis of hydrogentated 1D carbon nano-threads, Hy1DCNano, at tens of GPa (1 GPa = 10000 bar) from aromatic molecular systems is one of the most brilliant recent findings in high-pressure science. In these materials, the coordination of each carbon atom to the next nearest neighbours is similar to that of diamond. Therefore, Hy1DCNano combine the high tensile strength of diamond with the high flexibility of polymers, and many efforts are currently being undertaken to taylor some useful physicochemical properties by smartly modifying their local structure. We have synthesized double-core Hy1DCNano with the two cores being bound by a potentially conducting polymer backbone. The two cores also form a protecting sheath for the backbone. This material exhibits an optical bandgap of 1.74 eV, similar to polyacetyelene, the textbook conducting polymer; it is then very attractive as a potential organic semiconductor with simultaneous outstanding mechanical properties. The synthesis was achieved by reacting solid diphenylacetylene in diamond anvil cells, at 25−30 GPa and room temperature, and the materials were characterized by optical spectroscopy, synchrotron X-ray diffraction, and ab initio computer simulations.

The study was conducted by a collaborative team of researchers from INO-CNR, ICCOM-CNR, LENS, Università di Firenze, and Elettra Sincrotrone Trieste.

S. Romi, S. Fanetti, F. G. Alabarse, R. Bini, and M. Santoro, High-Pressure Synthesis of 1D Low-Bandgap Polymers Embedded in Diamond-like Carbon Nanothreads, Chem. Mater. 34, 2422–2428 (2022) https://doi.org/10.1021/acs.chemmater.1c04453.