Water Treatment Without Chemistry

Abstract

Thin-film boron-doped diamond coatings (BDD/Si) on boron-doped silicon substrates by means of a large-scale hot-filament chemical vapor deposition (HF CVD) process have been developed in order to be used as an innovative and efficient electrode material, mainly to promote electrochemical water treatment applications without using chemicals. Electrochemical performance from anodic as well as cathodic points of view results from extremely high chemical and mechanical stabilities as well as the largest known electrochemical window. They correspond to the primary conditions for an electrode in order to facilitate water processing like disinfection and reduction of the chemical oxygen demand (COD). These electrodes have the production capacity of the strongest chemical oxidizing agents in water i.e. hydroxyl radicals. They may also be responsible for the electrochemical generation of other strong oxidants like chlorine, ozone, peroxo-disulfates, peroxo-dicarbonates and hydrogen peroxide in many types of water, i.e. seawater, wastewater and fresh water, without the addition of any components.