Effect of zinc oxide films on the structure and photoluminescence properties of graphene-like nanoflakes

Abstract Graphene-like nanoflakes (GLNFs) were grown on silicon substrates pre-coated with carbon dots and zinc oxide films by hot filament chemical vapor deposition in the methane environment. The structure and composition of GLNFs were studied using field emission scanning electron microscope, micro-Raman spectroscopy and X-ray photoelectron spectroscopy, respectively. The results indicate that zinc oxide reduces the defects of GLNFs and the reaction of oxygen with carbon. The room temperature photoluminescence (PL) properties of GLNFs were investigated in a Ramalog system using 325 nm line of He–Cd laser as an excitation source. The PL results reveal that the GLNFs grown on the silicon substrate pre-coated with carbon dots and ZnO films generate a strong green PL band located at about 514 nm. However there is a difference in the PL intensity, which originates from the difference in structure of GLNFs and the distorted and non-bonding states formed in interfaces between GLNFs and ZnO film. The results can contribute to the synthesis of graphene-based nanomaterials and their applications in the area of optical devices.