The influence of multiple factors on the PtCo3 catalyst characteristics during the ORR process in proton exchange membrane fuel cells

The sluggish oxygen reduction reaction (ORR) and the expensive Pt-based catalyst cost of proton exchange membrane fuel cells (PEMFCs) restrict their commercial application. To address these problems, this paper uses a two-step sol-gel method to achieve low-cost and possibly large-scale production of catalysts. A preliminary study was conducted on the effects of various factors on catalyst performance, including carbon support type, annealing temperature, type of chloroplatinate cation, and loading precursor steps. The best and most suitable Na-750 sample's mass activity (MA) and specific activity (SA) reached 1.44 (0.168 mA/μgPt) and 3.03 (0.414 mA/cm2) times higher than that of commercial Pt/C, respectively. After an accelerated durability test (ADT) of 10000 potential cycles, the Na-750 sample also has a lower attenuation rate (39.9 %) than commercial Pt/C (47.9 %). The transmission electron microscopy (TEM) and X-ray diffraction (XRD) test revealed that the Na-750 sample prepared by the two-step sol-gel method has a smaller particle size (3.3 nm) and requires PtCo3 crystal without obvious phase segregation. This preparation method has a good prospect. It is hopeful that the activity and stability will be further improved through the ordering method in the future.