A combined graphene and periodic Au nanograte structure: Fundamentals and application as a flexible transparent conducting film in a flexible organic photovoltaic cell

Abstract

We report the fabrication of high performance transparent conducting films (TCFs) comparable to commercialized ITO by efficiently combining CVD-grown graphene with a 1D periodic Au nanograte (Au-NG). This high performance is attributed to the unique structure of the Au-NG (a high aspect ratio (approx. 20) and narrow width (approx. 15 nm)), which provides a density (sub mm pitch) that is much higher than that of the graphene domains and hence significantly improves the conductivity of polycrystalline graphene by providing direct charge carrier pathways between each graphene single domain without loss of transparency. In addition, the substrate embedding of the Au-NG provides flexibility, a flat surface, and excellent adhesion to polymer substrates for practical applications. This hybrid TCF was successfully applied to a flexible polymer solar cell, which was found to exhibit a power conversion efficiency, 6.38%, that is comparable to a device with commercialized ITO. (C) 2016 Elsevier Ltd. All rights reserved.