Electrochemical route for fluorinated modification of boron-doped diamond surface with perfluorooctanoic acid

An easy route was presented for fluorinated modification of boron-doped diamond (BDD) surface by electrochemical reaction with perfluorooctanoic acid (PFOA). In the present electrochemical system, PFOA decomposed on BDD anode to generate radicals containing fluorine, which reacted with the BDD surface and then were bonded to the surface. The introduction of fluorine was confirmed by XPS measurements. The fluorinated surface showed water repulsion and the contact angle was 115.2°. The electron-transfer rate of Fe(CN)63-/4- at the modified BDD surface was slower than the untreated surfaces, while the behavior of Ru(NH3)62+/3+ showed almost no change after fluorinated modification.