Cobalt octaethyltetrapyrazinoporphyrazine was synthesized and characterized by electronic absorption and magnetic circular dichroism spectroscopy. These spectroscopies and molecular orbital calculations within the framework of the Pariser-Parr-Pople approximation revealed that the effective π-conjugation system of octaethyltetrapyrazinoporphyrazine is smaller than phthalocyanines. For the first time, the electrochemical behaviour of cobalt octaethyltetrapyrazinoporphyrazine irreversibly adsorbed onto a glassy carbon electrode as a surface modifier is reported. The cobalt derivative/glassy carbon electrode showed catalytic activity for oxygen reduction. Surprisingly, the peak potentials for oxygen reduction at this electrode coincide well with those where CoII is reduced to CoI over the whole pH range, indicating that the active species for dioxygen reduction is CoI rather than the CoII species. A possible mechanism for the electrocatalysis of oxygen is discussed.
|Number of pages||8|
|Journal||Journal of Porphyrins and Phthalocyanines|
|Publication status||Published - 1997 Oct|
- Electrocatalytic reduction
- Glassy carbon
- Molecular orbital calculation
ASJC Scopus subject areas