Performance- and Durability-Enhanced Carbon-Skeleton Nanofiber Electrode with Pt3Co/C for PEMFCs

摘要

To enhance the performance and durability of proton-exchange membrane fuel cells (PEMFCs), we looked beyond the polymer-skeleton electrospinning electrode and developed a novel carbon-skeleton nanofiber electrode (the C-spun electrode) by a facile heat-treatment process. After thermal annealing at 600 degrees C, part of the disordered Pt3Co nanoparticles converted into an ordered intermetallic phase, with an apparently improved oxygen reduction reaction (ORR) activity (E-1/2 increased by 50 mV). Meanwhile, the polymers in the polymer-skeleton nanofibers were carbonized and transformed into carbon skeletons, which exhibited excellent corrosion resistance during extensive carbon corrosion testings (1.0-1.5 V, 0.5 V 1600 rpm, 30 000 cycles). In unit-cell tests, the C-spun electrode achieved an excellent performance of 8.207 W mg(pt)(-1) (H-2/air, 80 degrees C, 1 bar, 100% RH), which is higher than that of the previously reported electrodes with commercial Pt3Co/C. After 50 000 potential scanning cycles, a negligible performance loss was observed. The C-spun electrode provides a new direction for the next-generation electrodes of PEMFCs.