Rational design of a highly efficient Pt/graphene–Nafion® composite fuel cell electrode architecture

Abstract

High platinum requirements hinder the commercialization and wide adoption of polymer electrolyte membrane fuel cells (PEMFCs). Therefore, it is desirable to develop advanced electrode architectures that utilize Pt more effectively than the current designs. Herein, a novel electrode architecture based on Pt/graphene–Nafion® composite macroporous scaffold, prepared via facile freeze-drying approach, demonstrating ultra-high Pt utilization is presented. Within the electrode architecture, pores act as gas/liquid transport channels, whereas Nafion® ionomers act as proton carriers, and graphene sheets allow the conductance of electrons. By leveraging these tailored pathways for both mass and charges, a PEMFC prepared with this electrode architecture demonstrated superior performance, with a peak power density of 0.93 W cm⁻² and cathode mass specific power density of 6.2 W mg_Pt⁻¹. These values are 6-fold greater than those produced using a lamellar structure with the same mass loading of Pt/graphene–Nafion® and also 1.2-fold greater than the commercial Pt/C coated electrodes with the same Pt loading.