Continuous and scalable fabrication and multifunctional properties of carbon nanotube aerogels from the floating catalyst method

Abstract

In this work, we report on the effective implementation of the direct and scalable floating catalyst method to synthesize self-supporting carbon nanotube (CNT) aerogels at high deposition rates. Through the adaptable process conditions, the highly porous and ultralight CNT aerogels with densities ranging from 0.55 to 32 mg/cm3 are synthesized. The aerogels exhibit high porosity (>98%) and surface areas of up to 170 m2/g with tortuous pores easy accessible to molecules of interest. Their superior electrical conductivity (up to 106 S/m), in comparison with CNT aerogels produced through other methods, indicates high potential for energy applications. The thermal conductivity has been observed to be within the range of 0.127–0.137 W/m·K as a consequence of the ultralight structure. Polymer infiltration and subsequent curing do not disturb the three-dimensional percolating CNT network and constitute an accessible method for the production of various lightweight polymeric composites. The polydimethylsiloxane-based composites (4.5% wt) with electrical conductivity enhanced by ∼16 orders of magnitude and thermal conductivity double that of pure matrix are particularly promising for use in bio-integrated devices and flexible composites.