Excellent optoelectrical properties of graphene oxide thin films deposited on a flexible substrate by Langmuir–Blodgett assembly

Abstract

Transparent conductive films (TCFs) composed of ultra-large graphene oxide (GO) sheets are produced on a flexible poly(ethylene terephthalate) (PET) substrate using the Langmuir–Blodgett (L–B) assembly. The GO films are reduced using hydriodic (HI) acid followed by chemical doping treatments. The TCFs deliver excellent optoelectrical properties with a remarkable sheet resistance 1100 Ω sq⁻¹ at a transmittance of 91%, which is considered among the best. The plasma-treated PET substrate plays an important role in determining the chemistry and surface morphology of GO films: a combination of strong covalent bonds and π–π interactions between the GO and PET is revealed. The L–B assembly technique is suitable for the fabrication of flexible TCFs of optoelectronic devices on a large scale.