New transfer method of CVD-grown graphene using a flexible, transparent and conductive polyaniline-rubber thin film for organic electronic applications

In this work, a new fabrication method of large area electrodes for organic electronic applications, using a transparent and conductive graphene-rubber hybrid electrode is proposed. The rubber is a polymer blend composed of an elastomer, ethylene propylene diene monomer (EPDM), with in situ polymerized polyaniline (PAni), an intrinsic conducting polymer. The developed method is PMMA free, and the conductive and transparent rubber film is used to transfer the CVD-grown graphene directly to any substrate. After the transfer process, the graphene/EPDM-PAni electrode is ready to be used in organic electronic devices without any further removing or cleaning steps. Besides this advantage, the graphene/EPDM-PAni thin films have better electrical properties when compared to the PMMA conventionally transferred graphene. The graphene/EPDM-PAni hybrid electrode was characterized by various spectroscopic techniques, sheet resistance and roughness measurements. Organic photovoltaic devices (OPVs) using the graphene/EPDM-PAni as transparent electrode were fabricated and presented the same open circuit voltage (V-oc) of the similar ITO/glass based devices with lower short circuit current density (J(sc)) due to the higher electrode resistance. (C) 2015 Elsevier B.V. All rights reserved.