Carbon nanotube (CNT) fibers consist of a network of highly oriented carbon nanotube bundles. This paper explores the ingress of liquids into the contiguous internal pores between the bundles using measurements of contact angles and changes in fiber dimensions. The resultant effects on the internal structure of the fiber have been examined by WAXS and SAXS. A series of time-resolved experiments measured the influence of the structural changes on the electrical resistivity of the fiber. All organic liquids tested rapidly wicked into the fiber to fill its internal void structure. The local regions in which the nanotube bundles are aggregated to give a bundle network were broken up by the liquid ingress. For the range of organic penetrants examined, the strength of the effects on structure and electrical resistivity was correlated, not only with the degree to which the liquid reduced the nanotube surface energy, but also with the Hansen affinity parameters. The fact that liquid environments influence the electrical performance of these fibers is of significance if they are to replace copper as power and signal conductors, with added implications regarding the possible ingress of external insulating materials, and possibly also sensing applications.

We report a previously unseen non-ohmic effect in which the resistivity of carbon nanotube fibers immersed in polar liquids is modulated by the applied electric field. This behavior depends on the surface energy, dielectric constant, and viscosity of the immersion media. Supported by synchrotron SAXS and impedance spectroscopy, we propose a model in which the gap distance, and thus the conductance, of capacitive interbundle junctions is controlled by the applied field.

Rapidly jetting precursors in floating catalyst chemical vapor deposition produces monodisperse, metallic single-wall carbon nanotube fibres, irrespective of sulfur source.

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The behaviours of a range of polar and non-polar organic liquids (acetone, ethanol, methanol, N-methyl-2-pyrrolidone (NMP), carbon tetrachloride and water) confined to 2D graphene nanochannels with thicknesses in the range of 4.5 Å to 40 Å were studied using classical molecular dynamics and hybrid density functional theory. All liquids were found to organise spontaneously into ordered layers parallel to the confining surfaces, with those containing polar molecules having their electric dipoles aligned parallel to such surfaces. In particular, monolayers of NMP showed remarkable in-plane ordering and low molecular mobility, suggesting the existence of a previously unknown 2D solid-like phase. Calculations for polar liquids showed dramatically reduced static permittivities normal to the confining surfaces; these changes are expected to improve electron tunnelling across the liquid films, modifying the DC electrical properties of immersed assemblies of carbon nanomaterials.