Cyclic voltammetry measurements on boron- and nitrogen-doped diamond layers

Diamond layers with different amounts of boron and nitrogen were deposited on silicon substrates in a hot-filament CVD reactor. These layers are characterized by the simultaneous deposition of diamond and graphite. Electrochemical properties were measured in acid and basic solutions to gain knowledge about their potential application as electrodes for industrial wastewater treatment or for other fields of electrochemistry. While boron-doped layers show potential windows up to 4.3 V at 10 mA cm−2 in 0.1 N H2SO4 and 3.8 V at 50 mA cm−2 in 6 N NaOH, the size of the potential windows of mixed diamond-graphite layers decreases to 3 V in H2SO4 and 3.1 V in NaOH. During the electrochemical measurements, oxidation of graphite could be observed.