The 5-V Window of Polarizability of Fluorinated Diamond Electrodes in Aqueous Solutions

Heavily doped diamond films are quite actively studied for their promising applications in industrial as well as in fundamental electrochemistry (both for physicochemical studies and in the field of electroanalysis), because of their very high stability toward chemical and electrochemical oxidative attacks. Fluorinated diamond electrodes exhibit an exceptionally lower electrocatalytic activity toward reactions involving adsorbed intermediates, as a result of the F-termination of the surface dangling bonds. This feature allows the investigation of the widest range of potentials for an electrode material in aqueous solution, being limited only by the formation of free hydrogen [E° (H•/H2) = −2.3 VSHE] and hydroxyl [E° (•OH,H+/H2O) = 2.74 VSHE] radicals, at the two boundaries of the ∼5-V polarization window.