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Structural flexibility in a petroleum pitch-derived carbon material has been indirectly evaluated using X-ray diffraction (XRD), immersion calorimetry and inelastic neutron scattering (INS) measurements. Exposure of the carbon material to an organic solvent (e.g., n-nonane) gives rise to a large internal rearrangement, associated with a drastic re-ordering of the graphitic microdomains. These structural changes are also associated with a high flexibility of the internal porous network, as observed by inelastic neutron scattering measurements. The internal rearrangement and the structural flexibility could be responsible for the excellent performance of this kind of activated carbons in a wide variety of adsorption processes. Last but not least, the structural characteristics of these carbon materials composed of graphitic microdomains has been used to synthesize graphene “egg-like” flakes following a simple procedure based on exfoliation with organic solvents

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This paper focuses on the development of patterned graphene/substrate by means of green nanosecond pulse laser irradiation. Monolayer graphene samples supported on a Si/SiO 2 substrate were patterned using 532 nm laser irradiation under fluence conditions ranging from 31 mJ/cm 2 and to 4240 mJ/cm 2. Raman spectroscopy was used to investigate the effect of laser irradiation on the graphene. It was found that at 356 mJ/cm 2 selective ablation of the graphene occurs. However, at fluence values above 1030 mJ/cm 2 (when damage to the substrate is observed) no ablation of the graphene takes place. In contrast, its graphenic structure was found to have been modified. Only at fluence values where the ablation of the substrate occurs, is graphene eliminated in an area almost equivalent to that of the ablated substrate. In this case, additional damage to the graphene sheet edges is produced. The increment in the number of oxygenated functional groups in these regions, as measured by XPS spectroscopy, suggests that this damage is probably caused by thermal phenomena during the ablation of the substrate.

Dip coating and Layer-by-layer have been proven as effective deposition methods. Uncrosslinked and PPD crosslinked GO membranes have been successfully fabricated. Crosslinker impact is significant in enhanced membrane separation performance. Up to 100% MB contaminant removal was achieved for crosslinked membranes. PPD-GO crosslinked membranes are suitable to reuse for multiple cycles.