The synthesis and fluorescence quenching properties of well soluble hybrid graphene material covalently functionalized with indolizine

Chemically functionalized graphene–indolizine functionalized graphene (IMG) sheets, which can be well dispersed in different organic solvents over four months without obvious aggregation, are obtained through a 1,3-dipolar cycloaddition to graphene with pyridinium ylide. The properties of IMG sheets are investigated using a thorough set of measurements including UV–visible spectroscopy, Fourier transform infrared spectroscopy (FT-IR), thermogravimetric analysis (TGA), Raman spectroscopy, x-ray photoelectron spectroscopy (XPS), photoluminescence spectroscopy (PL), transmission electron microscopy (TEM), atomic force microscopy (AFM) and cyclic voltammetry (CV), and a tagging technique has exhibited the distribution of functional groups on the graphene surface. The IMG sheets show very strong quenching by a factor of ∼ 93.4% to that of indolizine, which is attributed to the fluorescence resonance energy transfer (FRET) from indolizine molecules to few-layer graphene sheets. The CV method also proved the catalytic properties of IMG sheets in some redox systems.