New insights into the “unzippering” mechanism of carbon nanotube dispersion via the “trigger” effect of small charged molecules

Abstract

In binary systems, the influence of different surfactants in carbon nanotube (CNT) dispersion and the dispersion efficiency remain unclear. This study compared CNT dispersion by sodium dodecyl benzene sulfonate (SDBS, small molecule), Triton X-100 (TX 100, large molecule), and their mixtures in single and mixed surfactant systems. A synergistic effect between SDBS and TX 100 was observed for CNT dispersion. The enhancement adsorption of TX 100 by SDBS indicated that SDBS likely acted as a trigger in the “unzippering” mechanism due to its small molecular size. The actual dispersion efficiency of CNT being higher than the theoretical value also proved the trigger effect of SDBS. However, when TX 100 concentration exceeded its critical micelle concentration, the synergistic effect disappeared. This result indicated that the trigger effect of SDBS probably did not occur because TX 100 directly encapsulated CNT in the form of large micelles.