Changes in a glassy carbon surface by the cathodic generation of free alkyl radicals mediated by a silver-palladium catalyst

The formation of free alkyl radicals by catalysis by silver-palladium alloy used as a fine suspension in the electrolysis bath led to the one-electron cleavage of primary alkyl bromides and iodides. Similar cathodic reactions do also exist with substituted benzyl bromides. In the presence of a carbonaceous-based substrate, such generated alkyl radicals can induce an efficient addition reaction with carbon leading to huge surface changes. A spectacular ablation of the carbonaceous surface even seems to occur (special case of glassy carbon) when large electricity amounts are used, producing a substantial loss of electrode mass. When graphite is used as the cathode material, evidence for channel formation together with a large amount of exfoliation is noticed. Surface changes were noticeably found to be dependent on the amount of electrical charge injected into the system. (C) 2011 Elsevier Ltd. All rights reserved.