Understanding Persulfate Production at Boron Doped Diamond Film Anodes

Role of sp3/sp2 ratio on the electrocatalytic properties of boron-doped diamond electrodes: A mini review

“…HClO 4 is then formed via the reaction between ClO 3 • and • OH at active carbon sites on BDD surface. Similar behavior was also observed during production of persulfate[40,41].The sp 2 sites [41] favors a strong interaction of • OH with HSO 4 − and SO 4 2− anions to form SO 4 − (principal intermediate) subsequently reacting and producing S 2 O 8 2− . The adsorption characteristic on highergraphite content BDD surface promotes a more efficient production of S 2 O 8 -2 due to its active behavior.…”

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

“…(7)) during electrolysis of aqueous solutions that in the presence of chlorides, they can oxidize this raw material successively to different oxochlorinated compounds (Eqs. (8)-(12)) [19,20].…”

“…For this reason, its occurrence has been related to the very efficient production of hydroxyl radicals on the BDD surface and their availability to react with chlorates [9][10][11] (which can be formed from chlorite and hypochlorite chemical and electrochemical reactions). At this point, the enhanced production of perchlorates with BDD 1 (which has the highest content of sp 2 carbon) has to be explained in terms of the adsorption of chlorates species onto the electrode surface [9] where they can be easily attacked by the hydroxyl radicals formed on the surface of diamond, like suggested for producing other oxidants [20]. It has to be taken into account that hydroxyl radicals have a very low lifetime and taking into account the typical mass transfer coefficients (about 10 − 5 m s − 1 ) they cannot be transported far away from the surface of the diamond electrode, but they have to act in a very small reaction cage on this surface.…”

Electrochemical removal of Reactive Black 5 azo dye using non-commercial boron-doped diamond film anodes

“…However, in the presence of organic matter, the radicals act as strong oxidizing agents to yield water, CO2 and other oxidation products [15]. BDD(•OH) + organic compounds → BDD + oxidized products + H + + e -Moreover, depending on the nature of the supporting electrolyte, other weaker oxidizing agents, including S2O8 2-formed by the oxidation of SO4 2-and HSO4 -ions, can be generated on the BBD surface and such species may also take part in oxidation reactions [16,17].The performance of a BDD electrode is related to the quality of the film and the adhesion of the film to the substrate. These parameters, along with the morphology, microstructure, stability and resistivity of the film, are influenced by the doping level.…”