A Supramolecular Cobalt–Porphyrin-modified Electrode, toward the Electroreduction of Co₂

Abstract

The electro-reduction of carbon dioxide was studied by using a glassy carbon electrode modified with Co(II)-tetrabenzoporphyrin as adsorbed layers or as a supramolecular system. In order to obtain the supramolecular electrode, 4-aminopyridine was chemically bonded to the electrodic surface. On this surface, a first layer of porphyrins was anchored by the pyridine as a fifth ligand. Packed on the first layer of porphyrins, a supramolecular system is formed. The electrode modified with physically adsorbed layers of porphyrins does not show catalytic response toward the electroreduction of CO₂. However, the supramolecular electrode is very stable and shows a high catalytic response.

Keywords:

• Supramolecular
• CO2
• Porphyrin
• Cobalt
• Electrode

Acknowledgments

We acknowledge the financial support of Fondecyt, project 1010695 and Conicyt (beca de apoyo tesis doctoral) AT-403139. Ramírez, Lucero and Riquelme acknowledge a Conicyt Doctoral Fellowship. Villagrán and Costamagna acknowledge a Conicyt-Fondecyt L.C. project 8010006.