One-pot synthesis of copper nanowire decorated by reduced graphene oxide with excellent oxidation resistance and stability

It is crucial to enhance anti-oxidation resistance of copper nanowires (Cu NWs) without degrading their transparent conductive characteristics. Here, reduced graphene oxide/copper nanowires (RGO/Cu NWs) with coating nanostructures were synthesized by a facile one-pot hydrothermal method. The copper nanowire was prepared by using copper (I) chloride as the precursor while the graphene oxide (GO) was reduced using the polyols as the reducing agent in order to obtain the coating structure, abandoning conventional tedious multi-step preparation processes. The microstructure and morphology of RGO/Cu NWs were characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), high-resolution transmission electron microscopy (HRTEM), selected-area electronic diffraction (SEAD) and X-ray photoelectron spectroscopy (XPS). The as-synthesized RGO/Cu NWs nanostructure is found to be almost coating structure of particle-free, high aspect ratio (L/D≈890) Cu NWs decorated with reduced graphene oxide (RGO), which accounts for the outstanding oxidation resistance. The stability tests show that the sheet resistance (R _S ) of the RGO/Cu NWs is almost unchanged over 20 days at room temperature or 5 h at 60 °C. What's more, the sheet resistance of the RGO/Cu NWs with coating structure only increases to 2.48 times after being heated for 150 min at 100 °C, which can directly indicate that the RGO/Cu NWs nanostructure has excellent anti-oxidation resistance and temporal stability. Also, the as-prepared RGO/Cu NWs transparent electrode has both low sheet resistance of 58.36 Ω/sq and high optical transmittance (87.12% @550 nm). The composite materials provide a better strategy to resolve the problem of being easily oxidized for Cu NWs and promote their wide practical applications.