Synthesis of carbon nanostructures by graphite deformation during mechanical milling in air

Abstract

In this investigation, time-dependent carbon nanostructures were prepared by high-energy ball milling in the air from elemental graphite powders. Scanning electron microscopy (SEM), X-ray diffraction (XRD), Raman spectroscopy (RS), and high-resolution transmission electron microscopy (HRTEM) characterized the ball-milled powders. XRD analysis showed that the crystal size decreased with the milling time. Raman spectra confirmed the presence of carbon nanostructures with sp² hybridization. Meanwhile, HRTEM images revealed different carbon morphologies during the milling time. During the different stages, it appears distortion of layers, large tapes, polyhedral morphologies, nanocapsules, and nano-onions. These carbon nanostructures occur in regions where there is carbon accumulation. In this way, the ball milling process in air conditions can promote distorted carbon and different morphologies.