The synthesis of carbon-based nanomaterials by pulsed laser ablation in water

Abstract

Pulsed Laser Ablation in liquid (PLAL) is considered as a robust and simple technique for producing nanoparticles (NPs) using lasers. The carbon-based nanoparticles were fabricated via the PLAL approach by irradiating a graphite target with a pulsed Nd:YAG laser of wavelength 532 nm. The graphite target was immersed in distilled water and irradiated for 10 min. The pulse length, reputation rate, and fluence were 6 ns, 10 Hz, and 0.4 J cm−2, respectively. The structural and physical properties of the synthesized NPs were investigated and analyzed using different characterization methods. For example, Transmission Electron Microscopy (TEM) images revealed diverse carbon nanostructures such as graphene nanosheets, nanospheres, nanospheres in the shape of a necklace, and nanotubes. The spectrum of Energy Dispersive X-Ray spectroscopy (EDX) confirmed successful synthesis of high purity carbon nanostructures. Moreover, the result of X-Ray Diffraction (XRD) Spectroscopy indicated the presence of reduced Graphene Oxide (rGO) with a (002) plane and the absence of Graphene Oxide (GO). The transmission spectrum from Ultraviolet-Visible (UV–vis) analysis showed a strong trough at 266 nm which is attributed to the presence of carbon nanostructures. Furthermore, Fourier-Transform Infrared Spectroscopy (FTIR) analysis demonstrated the vibration bonds related to carbon. The nanostructures produced were semi-stable with little agglomeration as was inferred from the results of the Zeta Potential. Finally, the Dynamic Light Scattering (DLS) analysis supported the TEM results. PLAL technique is proved to be a simple method for producing carbon-based nanomaterials. Moreover, the laser fluence was found to be an important factor which affects greatly the type of nanostructures that could be synthesized during laser ablation.