Fabrication and application of Diachem® electrodes

Conductive diamond coated electrodes have undergone intensive investigation over the past number of years. The unique electrochemical properties of diamond electrodes such as their extreme chemical resistance, even at high doping concentrations, and high overvoltage for water electrolysis opens the door to numerous applications. For the industrial use of extremely promising electrode material sufficient availability, also for large area electrodes is necessary. The development of large area DIACHEM(R) electrodes therefore has been performed on a range of base materials of numerous material geometries. For the production of these electrodes a large area HFCVD process is used which allows for reproducible coatings of substrates up to 50 X 100 cm. A doping with boron allows the reproducible setting of the resistivity of the diamond coating in the range of 5 to 100 m Omega cm. The extent to which DIACHEM(R) electrodes have been developed by now means that they can presently be applied in various industrial applications. The most important applications include: industrial waste water treatment, in particular the mineralization of toxic organic compounds; the disinfection of water; circulation systems with water which are only possible through use of an electrochemical recycling process; electrochemical synthesis, in particular from strong oxidising solutions and galvanic processes such as the recycling of chrome baths. Previous investigations have shown that the use of DIACHEM(R) electrodes results in either a significant improvement in the effectiveness or that the process was only possible through use of this particular electrode material. The user gains a combination of the typical advantages of the electrochemical process with the high efficiency of the DIACHEM(R) electrode which, in turn, has generated enormous interest in this particular material. In order to satisfy this interest, CONDIAS GmbH offers the DIACHEM(R) electrode commercially. (C) 2003 Elsevier B.V. All rights reserved.