Eleciroreduction of Oxygen on Pyrolytk Graphite Electrode with Adsorbed Layer of Cobalt Tetra.sulfonaied Phthalocyaninc In Acetonitrile and Dimethylformamide

摘要

The catjpdoc polarization characteristics indicate that the presence of a pre-adsorbed surface layer of CoTSPc innibits the reduction of O2 to O2- on an ordinary pyroiytic graphite electrode (OPG) in AN and DMF solution of 0. 1 mol/L, TEAP, The transfer coefficient a and the heterogeneous rate constant k for this reaction or, OPG with and without pre-adsorbed CoTSPc obtained by rotating disk electrode method were found to be fairly close to thar obtained by cyclic voltammetry. The a remains almost the same, bat the k de creases by a factor of 2-5 with CoTSPc as compared with OPG alone. The possible reason is that the adsorbed CoTSPc as an anion renders the effective potential diffaence less negative, which thus lowers the rase of O2 reduction.