We show that single-wall carbon nanotube (SWNT) fibers produced by the particle-coagulation spinning process possess a well-developed hierarchical skin-core structure. Primary SWNTs are organized in bundles that are 10-30 nm in diameter. The nanotube bundles form elementary filaments, which constitute the fiber skin, and a highly porous nanofelt, which fills the fiber core. The elementary filaments of ∼0.2-2 μm diameter are well aligned along the fiber axis and densely packed. The hierarchical pore structure organization determines unique wetting and sorption properties of SWNT fibers. Experiments with capillary condensation and droplet absorption of wetting fluids agree with the proposed skin-core model and can be used for pore structure characterization. The well-developed porosity and high surface area in conjunction with controllable electrical and mechanical functionalities make the SWNT fibers attractive materials for nanotechnologies, where wetting and sorption properties play an important role.
All Science Journal Classification (ASJC) codes
- Condensed Matter Physics
- Mechanical Engineering
- Materials Science(all)