Abstract: The effects of surfactant on aniline electropolymerization have been studied by cyclic voltammetry and potentiostatic step techniques.The experimental results show that the anionic micelle,i.e,sodium dodecylsulphate(SDS),can greatly catalyze the electropolymerization reaction of aniline and reduce its oxidation limited potential to +0.6 V(vs.SCE).In the anionic micellar media,the local concentration of aniline on the surface of electrode may be increased,and the aniline cation radicals are more stabilized in the hydrophobic micro-circumstance of micelle,which is available to avoid hydrolysis degradation of polyaniline(PAN) and enhance the stability of the PANfilm.The polymerized rate in the presence of 0.1 mol/L SDSincrease 25 times than that of solutions without SDS. When the solutions sontaining 10^-4 mol/LSDS,the PAN/SDSfilm growth via a two-dimensional(2-D) instantaneous nucleation under the electro transfer kinetic controlled,and the resulting film have a compact morphology.However,with the addition of cationic surfactant solution,e.g.cetyltrimethylammonium bromid(CTAB),the aniline electropolymerization is severely hindered due to the charge rejection between the aniline cation radicals and the cationic micellar.

Key words: Polyaniline, Surfactant, Micelle, Nucleation growth