Synthesis of polyaniline nanofibers with high electrical conductivity from CTAB–SDBS mixed surfactants

Mixed surfactant solution, containing cetyltrimethyl ammonium bromide (CTAB) and sodium dodecylbenzyl sulfonate (SDBS), is used to prepare polyaniline (PANI) with soft 1D structure and high electrical conductivity. The mixed surfactants in the reaction play double roles of soft templates and dispersion reagents. The influence of CTAB–SDBS ratio on the morphology and conductive property of PANI is investigated. Through varying the proportion of surfactants, uniformly branched nanofibers with higher aspect ratio and good dispersion are obtained, which possess the highest conductivity (0.102 S·cm−1). Moreover, FT-IR spectra are measured to explain the change of structure and conductivity under assistance of mixed surfactants. As a result, the mixed surfactants have significant effect on the electron density of whole structure as well as the PANI molecular orientation.

The novel method for synthesis of PANI nanofiber is proposed via a synergism of anionic surfactant (SDBS) and cationic surfactant (CTAB). The proportion of mixed surfactants has significant effect on the morphology and electrical conductivity. Uniform PANI nanofibers with the highest conductivity are obtained as 2:1 of CTAB/SDBS ratio.Figure optionsDownload as PowerPoint slideHighlights
► Novel method for synthesis of PANI nanofibers with high conductivity is proposed.
► SDBS–CTAB mixed systems play double roles of soft template and dispersion reagent.
► Morphology and conductivity can be optimized by varying CTAB/SDBS ratio.