Laser Ablation based "Green" Synthesis of multilayer Graphene and Graphene Oxide nanosheets

In this experimental investigation, a simple and efficient technique is presented for the carbonic nanostructures fabrication-in particular, Graphene Oxide (GO) and Graphene nanosheets- based on the pulsed laser ablation of graphite target inside the Cetyltrimethylammonium bromide (CTAB) (0.1 M) and liquid nitrogen environments using the pulsed nanosecond Q-switched Nd:Y3Al5O12 (Nd:YAG) laser at 532 nm. X-ray diffraction (XRD) pattern, Raman spectrum, Transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FT-IR) and Field emission scanning electron microscopy (FE-SEM) were used to characterize the ablation products. Results exhibit that the graphene nanosheets produced in liquid nitrogen medium are multilayer, includes the largest SP2 domain size and the least structural defects. In addition, two categories of graphene nanosheets and carbon nanoparticles were observed in TEM images of produced sample in this cryogenic medium. Furthermore, XRD, FT-IR and Raman analyses indicate that graphene is oxidized in CTAB solution owing to existence of oxygen molecules in ablation environment. Our experimental results can be useful guidance toward the production of graphene nanosheets with desired attributes.