Graphene is often referred to as bi-, tri- or few-layered (4 to 10 layers), despite it being single-layered. Two commercial graphite samples (G and GE) and three commercial graphene samples (G1, G2, and G3) were characterized by Raman spectroscopy, scanning electron microscopy, X-ray diffractometry and atomic force microscopy. The structural similarities and differences between graphite and graphene were compared with literature information. A mixture of hexagonal (2H) and rhombohedral (3R) phases were identified in samples G1, G2, G3, and GE by X-ray diffraction. Graphene is observed to differ from graphite-based on Raman spectroscopic studies at room temperature. Atomic force microscopy on graphene films at 514 nm radiation showed ~ 3, 7, and 9 layers for G1, G2, and G3, respectively.
Graphene; Graphite; Crystal structure; Nanomaterials; Raman spectroscopy; Atomic force microscopy; X-ray diffractometry; Scanning electron microscopy