Optical properties of carbon nanostructures produced by laser ablation method in different liquid environments have been studied experimentally. In this work we used a 7 ns fundamental wavelength of pulsed Nd:YAG laser at 1064 nm and 10 Hz repetition rate to produce carbon nanostructures including graphene in distilled water, acetone, alcohol, and CTAB. Structure and morphology of carbon nanostructures were studied using their UV-Vis-NIR spectrum, TEM images, and Raman scattering spectrum. Results show that in our experimental condition distilled water was the most capable medium for producing graphene. Color of suspensions varied with the amount of carbon nanoparticles in the suspension while the bandgap energy of samples decreases with increasing the amount of graphene.

Effects of liquid environment on the characteristics of graphene nanosheets produced by the laser ablation method have been studied experimentally. The fundamental wavelength of a pulsed Nd:YAG laser at 1064 nm with 7 ns pulse width and 5 Hz repetition rate was employed to irradiate a graphite target in distilled water, liquid nitrogen, alcohol, acetone, and two concentrations of cetyltrimethylammonium bromide. Produced carbon nanostructures were diagnosed using Ultraviolet-Visible-Near Infrared and Fourier transform infrared spectroscopy, x-ray diffraction, Raman spectroscopy, transmission electron microscopy, and field emission scanning electron microscope images. Results show that different carbon nanostructures such as carbon nanoparticles and fluorine, as well as graphene nanosheets were formed in various liquid environments. The size and morphology of nanostructures strongly depends on the liquid environments and, among these liquids, water is the most capable one to produce graphene nanosheets.