We present a rational and general method to fabricate a high-densely packed and aligned single-walled carbon-nanotube (SWNT) material by using the zipping effect of liquids to draw tubes together. This bulk carbon-nanotube material retains the intrinsic properties of individual SWNTs, such as high surface area, flexibility and electrical conductivity. By controlling the fabrication process, it is possible to fabricate a wide range of solids in numerous shapes and structures. This dense SWNT material is advantageous for numerous applications, and here we demonstrate its use as flexible heaters as well as supercapacitor electrodes for compact energy-storage devices.

The mechanism and kinetics of the pressure-induced polymerization of acetylene were studied by Raman spectroscopy. The polymerization reaction occurred in the orthorhombic phase at room temperature and pressures above 3.5 GPa. Dominant formation of trans-polyacetylene suggested that the monomer underwent trans opening of the triple bond and polymerized along the diagonal of the bc plane of the unit cell. The reaction was described as an idealized one-step and one-dimensional growth process by an Avrami equation with an exponent 1.34.

A cubic BC,.,N solid solution (c-BC,.,N) was synthesized in 18% yield by shock-compression of a hexagonal BC2.5N compound. c-BC2.,N was confirmed to have a diamond structure without a long range order of atomic arrangement. The material is a polycrystal composed of microcrystals of 5-20 nm in size. All constituent atoms are teterahedrally coordinated, giving C-C, C-By C-N, and B-N bonds, and are homogeneously distributed on the lattice planes rather than showing a full short range order of atomic arrangement.

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Cyanoacetylene underwent polymerization reaction in a solid phase at pressures above 1.5 GPa. The Raman study of the reaction product showed that the polymer had a conjugated linear backbone with CN pendant groups. The Raman spectra for this substituted polyacetylene demonstrated a resonance behavior similar to that reported for trans-polyacetylene. The optical gap associated with the π–π* transition in the conjugated system was smaller than that of trans-polyacetylene, probably due to the resonance interactions between the CN triple bonds and the conjugated double bonds.