A Self-Assembly Route to an Iron Phthalocyanine/Reduced Graphene Oxide Hybrid Electrocatalyst Affording an Ultrafast Oxygen Reduction Reaction

Graphene oxide (GO) is an attractive freestanding support that can be decorated with ultrathin organic layers for facile and low-cost fabrication of novel devices with controllable functional properties and microstructures. Here, it is reported that a hybrid material consisting of an ultrathin iron phthalocyanine (FePc) layer self-assembled on reduced graphene oxide (rGO) exhibits excellent catalytic activity that is superior to that of commercial Pt/C for an oxygen reduction reaction (ORR). During solution processing, the FePc layer is first self-organized onto GO sheets and then reduced electrochemically to form an FePc/rGO hybrid electrocatalyst. Kinetics studies reveal that the hybrid architecture affords an ultrafast ORR rate caused by a strongly dominant four-electron process, and the durability of the catalyst shows significant improvement by forming the hybrid structure. Spectroscopic studies suggest that these advantages are afforded by synergistic effects between FePc and rGO, which are enriched by the hybrid structure and the appropriate reduction step.