Properties of diamond electrodes for wastewater treatment

Boron-doped diamond films are deposited by large-area hot filament CVD (HFCVD) on silicon and different industrial electrode materials, such as titanium, zirconium: niobium, tantalum, tungsten and graphite, with areas up to 50 x 60 cm(2). Boron-doping levels ranging from 50 ppm to several thousand ppm are realised using trimethylborate. These electrodes are characterised in terms of their material and electrochemical properties by scanning electron microscopy (SEM), Raman spectroscopy, secondary ion mass spectrometry (SIMS) and cyclic voltammetry. The oxidation of organic compounds in water is studied using different alcohols and organic acids. In the presence of oxygen, organic molecules are oxidized even at very low concentrations to CO2 in the absence of large amounts of other detectable by-products