Investigation of FePc Nanoribbon as ORR Catalyst in Alkaline Medium: A DFT Based Approach

Abstract

The oxygen reduction reaction (ORR) plays an important role in fuel cell devices and holds a major place in the field of electrocatalysis. The reaction mechanism has, so far, been explored with the Pt electrode, which, however, due to its high cost and limited resources, limits the practical application of Pt in fuel cell. As an alternative to Pt electrode, metallophthalocyanine is currently under research focus as suitable electrocatalysts, because of the presence of delocalized and conjugated π bond in metal-phthalocyanine, making it suitable for oxidation and reduction reaction. Among various phthalocyanines, Iron Phthalocyanine (FePc) shows best catalytic activity toward reduction of oxygen. Therefore, in this report, we have studied for the first time the electronic structure of FePc nanoribbon as well as its electrochemical activity in alkaline solution. The ORR activity for FePc nanoribbon is comparable to the state-of-the-art Pt/C catalyst. First principle DFT calculation suggests the hybridization between dz2 orbital of Fe 3d with 2p orbital of O in adsorbed O2 molecule. Our results demonstrate that FePc nanoribbon may be used as a promising electrocatalyst in fuel cells as an alternative toPt-based catalyst.