Herrmann, I. ;Koslowski, U.I. ; Radnik, J. ; Fiechter, S. ; Bogdanoff, P.: Preparation and structural analysis of heat treated Co-and Fe-porphyrines as cathode catalysts for the oxygen reduction reaction. ECS Transactions 13 (2008), p. 143-160
10.1149/1.3039772
Abstract:
The following work presents the preparation and investigation of pyrolysed Co-porphyrine as an electrocatalyst for the oxygen reduction reaction (ORR) in acid media. A new preparation method which needs no addition of carbon supports, allows the structural investigation of the pyrolysis products by XPS, Raman spectroscopy and X-ray diffractometry without any interferences. Rotating Disc Electrode measurements reveal the high ORR activity which is mainly caused by a well developed porosity and a suitable molecular structure of the formed carbon. Thermogravimetric investigation of the pyrolysis process shows that the addition of sulphur influences the carbonization of the porphyrine in a favorable way. It has been found that extended graphene layers present a particularly suitable matrix for highly active catalytic centers.