p-Xylylenediamine intercalation of graphene oxide for the production of stitched nanostructures with a tailored interlayer spacing

The p-xylylenediamine intercalation reaction of graphene oxide (GO) has been investigated as a convenient and simple approach to the preparation of pillared-type graphene-based materials with a tailored interlayer spacing. Powder X-ray diffraction studies in combination with thermo-gravimetric analyses and swelling tests have demonstrated the generation of a constrained system (covalently ''stitched'') along the c-axis exhibiting a considerably increased interlayer distance compared to the starting, pristine GO. X-ray photoelectron spectroscopy measurements were consistent with a cross-linking process involving oxygen functional groups (basically epoxides) typically present at the GO basal plane. Finally, nitrogen adsorption-desorption isotherms (BET plots), transmission electron microscopy and scanning electron microscopy micrographs have been used to underline the increased specific surface area and porosity of the amine intercalated material, as well as to emphasize the morphological differences between the two samples (pristine GO and intercalated material). The production of tailored GO-based nanostructures with improved chemico-physical properties paves the way towards the multigram synthesis of porous carbon- based nanomaterials.