Intercalation and stitching of graphite oxide with diaminoalkanes

The intercalation reaction of graphite oxide with diaminoalkanes, with the general formula H2N(CH2)(n)NH2 (n = 4-10), was studied as a method for synthesizing pillared graphite with tailored interlayer spacing. Interlayer spacings from 0.8 to 1.0 nm were tailored by varying the size of the intercalant from (CH2)(4) to (CH2)(10). X-ray diffraction and infrared spectroscopy were used to confirm intercalation, and the frequency of the CH2 stretch confirmed that the intercalants are in a disordered state, with an important contribution from the gauche conformer. Sequential intercalation of diaminoalkanes followed by dodecylamine demonstrated the inability of these stitched systems to undergo expansion along the c-direction, indicative of cross-linking. Finally, the reaction of graphite oxide with diaminoalkanes under reflux and for extended periods (> 72 h) resulted in the chemical reduction of the graphite oxide to a disordered graphitic structure.