A mixed valence diiron(II/III) complex with the ligand 2,6-bis{bis[(2-pyridinylmethyl)amino]methyl}-phenol (bppH) has been covalently anchored onto graphene using a mild in situ microwave-assisted diazonium coupling through an aryl amino precursor and isoamyl nitrite. A dinuclear iron complex is then formed by complexation of the grafted bppHgraphene material with iron(II) in the presence of dioxygen. X-ray photoelectron spectroscopy (XPS), atomic force microscopy, cyclic voltammetry, scanning transmission electron microscopy, energy-dispersive X-ray spectroscopy and electron paramagnetic resonance (EPR) spectroscopy confirms the formation of the anchored ligand and derivative diiron complexes. Semi-quantitative XPS analysis shows an average bppH ligand bulk loading of 0.33 mmol/g, corresponding to a significant 20.7 wt% of the functionalized material consisting of grafted moieties. EPR measurements reveal the existence of a strong isotropic S = 1/2 spin center associated with the graphene lattice, together with a much weaker S = 5/2 signal, associated with the iron(III) center of the grafted complex. The grafted complex is redox-active with surface-confined Fe II Fe II → Fe II Fe III (+0.56 V vs. NHE), Fe II Fe III → Fe III Fe III (+0.73 V) and Fe III Fe III → Fe III Fe IV (+0.95 V) redox processes accessible, with an estimated surface coverage of 58 pmol cm-2 established from the electrochemical measurements.