ZnO Nanorod−Graphene Hybrid Architectures for Multifunctional Conductors

Abstract

We report ZnO nanorod−graphene hybrid architectures (ZnO−G HAs) composed of regular arrays of ZnO nanorods formed on few-layer graphene films transferred to transparent and/or flexible substrates. The ZnO−G HAs exhibited a high current flow reaching ∼1.1 mA at an applied bias of 1 V and good optical transmittance in the range of 70−80%, comparable to those of a graphene layer. In addition, cathodoluminescence images and photoluminescence spectra of the ZnO−G HAs showed distinct light emission involving optical transitions in the ZnO nanorod array. Moreover, a bending test demonstrated that the ZnO−G HAs exhibit excellent mechanical flexibility and structural stability for the bending radius down to ∼4 mm. Our results suggest that the 1D−2D HAs provide unique and multiple functions as can be applicable for next-generation electronic and optoelectronic systems.