Synthesis of conducting polyaniline nanofibers from single and binary dopant agents

Conducting polyaniline nanofibers (nf-PANI) were successfully synthesized by simple polymerization of aniline in presence of single and binary dopant agents. Strong hydrochloride acid (HCl), two weak organic acids (poly acrylic acid, PAA, 2-acrylamido-2-methyl-1-propanesulfonic acid, AMPSA) and one anionic surfactant (sodium dodecyl sulfate, SDS) were used to form the binary dopant agents. The binary dopant agent PAA modified the morphology of the single doped PANI, whereas AMPSA and SDS modified the dimensions of the nanofibers: the length size single nanofibers is reduced 1.72 times with binary-doped AMPSA and increased by a factor of 0.7 with SDS. The surface roughness of the films decreases when the dimensions of the nanofibers increase: PANI-SDS film is flatter than PANI-AMPSA film. In general, the conductivity of the single-doped PANI nanofibers (nf-PANI-HCl) was improved by one order of magnitude with binary dopant agents (HCI-PAA, HCl-AMPSA, HCl-SDS). The influence of the binary dopant agents in the nf-PANI-HCl properties is analyzed by Transmission Electron Microscope (TEM), Atomic Force Microscopy (AFM), UV-VIS absorption spectra, thermogravimetric analysis (TGA) and Fourier-Transform infrared spectra (FT-IR).