Tuning the dispersibility of multi-walled carbon nanotubes in nanofibrillated cellulose: a tactical design of anionic surfactant ionic liquids

Carbon nanomaterials composite is often made with the aid of ionic surfactants to provide stable system. Despite the existing literatures, there is still lack of consensus regarding the surfactant design, aggregation structure, and corresponding dispersion quality. Here, cellulose conductive papers were prepared by combining multi-walled carbon nanotubes (MWCNTs) dispersion stabilized by ionic surfactants and/or anionic surfactant ionic liquids (SAILs) with nanofibrillated Kenaf (Hibiscus cannabinus L.) cellulose fiber. The SAILs were systematically synthesized from commercial surfactants sodium dodecylsulfate (SDS), sodium dodecylbenzenesulfonate (SDBS) combined with a 1-butyl-3-methyl-imidazolium (BMIM) cation. The efficiency of each compound was measured in terms of the nanocomposite papers electrical conductivities. The SAILs promoted ∼ 6 orders of magnitude enhancement compared to composite papers without stabilizer. Field emission scanning electron microscopy (FESEM) revealed more individualized nanotubes when SAILs were present. The results highlight the importance of surfactant design in achieving optimal dispersion and performance in carbon nanomaterials composites.