Enhanced oxygen reduction performance by novel pyridine substituent groups of iron (II) phthalocyanine with graphene composite

In this paper, a novel iron (II) tetrapyridyloxyphthalocyanine decorated graphene (FeTPPc/Gr) is synthesized through a simple solvothermal method. The catalytic performance of the fabricated FeTPPc/Gr for the oxygen reduction reaction (ORR) is accessed by cyclic voltammetry (CV), linear sweep voltammetry (LSV) and i-t chronoamperometry methods. The FeTPPc/Gr composite catalyst for the ORR displays an enhanced electrocatalytic activity compared with other FePc/Gr catalysts. More importantly, the proposed FeTPPc/Gr catalyst towards the ORR outperforms the commercial Pt/C catalyst in terms of higher diffusion-limiting current, more positive onset potential and half-wave potential, better stability and tolerance to methanol crossover. The improved ORR performance is attributed to the activity of peripheral pyridine substituents in the FePc, which facilitate O-2 absorption and increase the additional active sites. Based on our experimental results, designing novel metal-N-4 macrocycles and incorporating them into graphene or graphene derivatives, with both optimal activity and durability for the ORR, may hold great promise for application in alkaline direct methanol fuel cells (DMFCs). (C) 2015 Elsevier B.V. All rights reserved.