In situ template polymerization of aniline on the surface of negatively charged TiO2 nanoparticles

The in situ oxidative template polymerization of aniline was performed successfully on the surface of negatively charged titania (TiO2) nanoparticles with a mean diameter of 40 nm using ammonium persulfate and a Chem-Solv solution at pH 1 and 25 degrees C. SEM showed that the resulting polyaniline (PANI)/TiO2 composites were well dispersed in solution due to the electrostatic repulsion force. Ultraviolet/visible spectroscopy, thermogravimetric analysis, Fourier-transform infrared spectroscopy, and cyclic voltammetry showed that the optical, thermal, and electrical properties of PANI/TiO2 composites were quite different from those of pure PANI or TiO2, which was attributed to the strong interaction between the two components. The conductivity of the PANI/TiO2 composite was estimated to be 0.91 x 10(-1) S/cm at 25 degrees C in the range of semiconductor. (C) 2009 Elsevier B.V. All rights reserved.