EQCM and RDE/RRDE Study of Soluble Iron Phthalocyanine Bifunctional Catalyst for the Lithium-Oxygen Battery

Abstract

Soluble iron phtalocyanine (FePc) has been studied as a bifunctional catalyst for the oxygen reduction reaction (ORR) and oxygenevolution (OER) in lithium air cathodes by means of electrogravimetry with shear wave dissipation, cyclic voltammetry (CV) androtating ring disk electrode (RRDE). The oxygen reduction reaction (ORR) has been studied on Au in oxygen saturated TBA-PF6in DMSO and LiTFSI-DMSO electrolyte for increasing concentration of Fe-phtalocyanine as redox mediator for the two-electronORR at 2.2 V and the oxidation of the surface Li2O2 product below 3.6 V vs. Li/Li+ where the solvent is stable. The soluble FePccatalyst promotes the ORR solution phase mechanism.