Facile and rapid production of conductive flexible films by deposition of polythiophene nanoparticles on transparent poly(ethyleneterephthalate): Electrical and morphological properties

In this work, polythiophene (PTh) nanoparticles were successfully deposited on poly(ethyleneterephthalate) (PET) substrate as thin film by a facile and rapid chemical oxidative deposition method using a binary organic solvent system in the presence of N-cetyl-N,N,N-trimethylammonium bromide (CTAB) as cationic surfactant. The electrical conductivity of PTh nanoparticles deposited on PET was optimized by adjusting the surfactant/oxidant/monomer molar ratio, monomer concentration and time of polymerization. Resulted film was conductive, transparent and flexible which can be used in electronic devices such as OLEDs. Electrical conductivity for the un-doped deposited PTh nanoparticles at oxidant/monomer molar ratio of 5:1 at 0 °C polymerized for 12 min was measured to be 1.18×10−2 S/cm. The effect of oxidant and monomer concentration on polymerization yield was also investigated. The structural confirmation and transparency of the PTh nanoparticle coated PET films were characterized by FTIR and UV–vis spectroscopy, respectively. Field emission scanning electron microscopy (FESEM), laser particle size analysis and transmission electron microscopy (TEM) were employed for surface morphology and size distribution measurements of PTh nanoparticles. The results showed that the PTh nanoparticles are deposited as globular aggregates with average size of about 50 nm on PET.