Electrochemical Study of Complex Formation of Cerium (IV) Ion with Glycyl-Glycine and Glycyl-Valine

Cyclic voltammetry can be used to determine the relative stability of Ce4•tJ+ complexes which has been less accessible by other techniques. Shifts in the anodic and cathodic peak potentials of Ce4•tJ+ -L and thereversibility of the electrochemical processes were studied as a function of concentration of the ligands. Thecyclic voltammograms of Ce4•IJ+ obtained at different scan rates are quasireversible with a formal redox potential of E 112= 0.95975 V in 0.5 M H2S04 solution. The voltammograms of Ce4+tJ•-g lycyl-glycine (Ce4 • 13•-gly gly) and Ce4+IJ+- glycyl- valine (Ce4+IJ+ -gly val) show a reduction wave negatively shifted relative to the reduction wave of Ce4 • 13 • . The reversibility of the Ce4 • /Ce3 • couple improved with the increase of scan rates