Understanding active chlorine species production using boron doped diamond films with lower and higher sp3/sp2 ratio

The present study was motivated by the reports that promote the use of boron doped diamond (BDD) anode for electrochemical disinfection. The discussion about the production of undesirable active chlorine species on diamond films is still open. For this reason, the influence of sp(3)/sp(2) ratio on the performance on the evolution of chlorine-related species was investigated by polarization and electrolytic techniques in order to establish whether their formation and consumption related to either chemical or electrochemical reactions. The results demonstrated that dissolved Cl-2, ClO2-, ClO2, ClO3- and ClO4- species can be electrochemically formed at both BDD electrodes. However, the concentration trends are different, indicating that the relation of sp(3)/sp(2) ratio has a key role in the electrochemical route to produce ClO3- and ClO4-. (C) 2015 Elsevier B.V. All rights reserved.