Formation of Graphene Features from Direct Laser-Induced Reduction of Graphite Oxide

Graphene features are produced via continuous-wave (532 nm) or pulsed (532 and 355 nm) laser excitation of graphite oxide. Micro-Raman spectroscopy of these laser-irradiated areas reveals D and G bands on the edges and the 2D band characteristic of graphene in the central laser-irradiated zones. I D / I 2D ratios vary with laser power and background gas. An I D / I 2D ratio of ∼0.17 is obtained using continuous-wave excitation in a N 2 background, indicating a dominance of graphene optical signatures. The I D / I G ratio obtained for the same region indicates a particle size or interdefect distance of ∼40 nm. This technique could be useful for laser or lithographic patterning of graphene features.