Modulating SWCNT–silica interactions for enhanced dispersibility and hybrid cryogel formation

Single walled carbon nanotubes (SWCNTs) form a special class of carbon materials with high electric and thermal conductivity. Ordinary SWCNTs exist in the form of bundles, primarily because of intertubular van der Waals attraction. Here we show that silica nanoparticles (NPs) with tunable surface energy can be used as efficient aqueous dispersant for SWCNTs. A subsequent controlled solvent-evaporation leads to the formation of SWCNT–silica hybrid cryogels. We characterize cryogels using gas/vapor adsorption and electric conductivity measurements and show that their porosity and conductivity can be fine-tuned by altering the silica-to-SWCNT relative concentration. We believe that the SWCNT–silica hybrid cryogels can be used as a precursor for fabricating functional electrodes for advanced energy storage devices.