Interactions between an aryl thioacetate-functionalized Zn(II) porphyrin and graphene oxide

Boyang Mao, David G. Calatayud, Vincenzo Mirabello, Benjamin J. Hodges, José Alberto Ribeiro Martins, Stanley W. Botchway, J. M. Mitchels, Sofia I. Pascu

OAI: oai:purehost.bath.ac.uk:publications/d3590943-6591-4de1-990d-6be4b7547fa4 • DOI: https://doi.org/10.1002/adfm.201504147

The surface modification of graphene oxide (GO) is carried out via the supramolecular functionalization route using a Zn(II)-porphyrin which is soluble in common organic solvents on basis of long alkyl chains present at the exocyclic positions. This acts as a dispersing agent and decorates the surface of the graphene oxide uniformly, giving rise to a new nanohybrid denoted Zn(II)-porphyrin@GO. The resulting Zn(II)-porphyrin@GO nanohybrid forms a stable dispersion in ethanol (as characterized by several different spectroscopic techniques such as UV–vis, Fourier transform infrared, Raman). The morphology of Zn(II)-porphyrin@GO nanohybrid is investigated by atomic force microscopy (AFM) and transmission electron microscope (TEM)/selected area electron diffraction. Both TEM and AFM measurements indicate that the Zn(II)-porphyrin self-assemble onto the surface of graphene oxide sheets. Steady-state and time-resolved fluorescence emission studies in the dispersed phase, and as a thin film, point toward the strongly quenched fluorescence emission and lifetime decay, suggesting that energy transfer occurs from the singlet excited state of Zn(II)-porphyrin unit to GO sheets.