Poly(3,4-ethylenedioxythiophene)/TiO₂ nanocomposites prepared in the presence of surfactants in binary solvents

Abstract

In this research, a new facile and efficient route has been employed to prepare poly(3,4-ethylenedioxythiophene)/titanium dioxide (PEDOT/TiO₂) nanocomposites using chloroform-acetonitrile binary solvents. Two homogenized and stabilized chloroform-based nanofluids were separately prepared with titanium dioxide nanoparticles in the presence of two anionic and cationic surfactants, i.e. sodium dodecylbenzene sulfonate (SDBS) and tetradecyltrime-thylammonium bromide (TTAB) by sonication. Next, 3,4-ethylenedioxythiophene (EDOT) monomer was added to these nanofluids. A solution of iron (III) chloride oxidant in acetonitrile was then slowly poured into the previous mixture. The chemical oxidative polymerizations resulted in the preparation of PEDOT/TiO₂ in a medium of the two mentioned miscible organic solvents. To compare the results obtained, pure PEDOT as a reference was also prepared by a similar manner to that of used to prepare PEDOT/TiO₂ nanocomposites. UV–vis diffuse reflectance spectra (DRS) were utilized to investigate the effect of the incorporated nano-TiO₂ particles on optical properties of PEDOT. X-ray diffraction (XRD) patterns obviously showed the characteristic peaks of embedded TiO₂ nanoparticles on the diffractogram of the resulting PEDOT. Surface morphology of the nanocomposites was evaluated by scanning electron microscopy (SEM) analyses. Transmission electron microscopy (TEM) images demonstrated that the TiO₂ nanoparticles were uniformly dispersed in both PEDOT bulks. Thermogravimetric analysis (TGA/DTG) clearly showed that both PEDOT/TiO₂ nanocomposites are more stable toward heat compared with the pure PEDOT sample.