Preparation of conductive flexible films by in situ deposition of polythiophene nanoparticles on polyethylene naphthalate

Deposition of Polythiophene (PTh) nanoparticles on the unmodified and modified polyethylene naphthalate (PEN) films via solution based in situ chemical polymerization was investigated as conducting transparent anode electrodes in order to produce transparent conducting films with applications in opto-electronic devices, such as flexible displays. The surface of PEN films were modified by different methods. Surface modification was carried out using Piranha and alkaline (KOH) solution and ultraviolet (UV) radiation as a physical method. Combination of chemical and physical treatments (Piranha and UV) was also examined. The effect of surface modification methods on the properties of the in situ deposited PTh nanoparticles was studied. It was found that electrical conductivity increases ~20 times in effect of modification of PEN by the examined methods. Highly ordered morphology of PTh nanoparticles were observed by field emission scanning electron microscope (FESEM) in the case of surface modification by UV radiation. Hydrophilicity, transparency and surface morphology of the PEN films were found to be influenced by surface modification techniques as well.