Porphyrin counter anion in imidazolium-modified graphene-oxide

Imidazolium-modified graphene-oxide hybrid materials have been prepared and characterized by complementary spectroscopic, thermal and microscopy techniques, while the counter anion of the positively charged imidazolium fragment identified by energy dispersive X-ray analysis. Moreover, the counter anion has been exchanged, thus (i) allowing to modulate the wettability of the material (i.e., switchable hydrophilic vs lipophilic counter anion), resulting on switching the dispersibility of the hybrid material from aqueous to organic solvents, based on the nature of the anion, and (ii) introducing an extra functionality, such as a photoactive anionic porphyrin. The latter has allowed the performance of optical and electrochemical studies, which denote that some interaction takes place between the porphyrin counter anion and graphene-oxide. Finally, the energy gap has been calculated from the reduction and oxidation potentials of the hybrid material. (C) 2009 Elsevier Ltd. All rights reserved.