ELECTROCHEMISTRY OF MACROCYCLES AND THEIR CATALYTIC ACTIVITY FOR O//2 REDUCTION.

An interesting question is how the Fe- and Co-TsPc are adsorbed on the electrode surface and particularly whether they are adsorbed as a dimeric oxygen bridged complex. The interaction of adsorbed Co-TsPc and Fe-TsPc with the substrate electrode surface (graphite, Pt and Au) has been studied using visible reflectance spectroscopy (6). The reflectance spectra of the adsorbed Fe-TsPc and Co-TsPc monolayers undergo substantial changes at constant potential with the introduction of O//2 into the electrolyte, thus providing evidence for the formation of an O//2 adduct. The Raman spectra of these species, adsorbed on Ag resemble those of the solution phase species. Recently the Raman spectra have been examined with these complexes adsorbed on single crystal Ag surfaces without activation or anodic treatment of the electrode (8). On the basis of polarization-depolarization measurements, the adsorbed species appear to involve a perpendicular orientation.