Oxygen Electroreduction on Nanoscale Pt/[TaOPO_4/VC] and Pt/[Ta_2O_5/VC] in Alkaline Electrolyte

摘要

The ORR on Pt in an alkaline electrolyte is studied for the impact of support effects. Platinum nanoparticles are supported on nanoscale tantalum oxyphosphate or tantalum oxide films on Vulcan carbon (VC) to make either Pt/[TaOPO_4/VC] or Pt/[Ta_2O_5/VC] electrocatalysts, which were then characterized with BF-STEM. Their ORR activity was determined by RDE methodology in 0.10 M KOH electrolyte. The Pt mass activities of the Pt/[TaOPO_4/VC] and Pt/[Ta_2O_5/VC] electrocatalysts are both approximately 250 mA mg_(pt)~(-1) at 0.925 V, or about 2 x greater than that of a commercial Pt/VC electrocatalyst (120 mA mg_(pt)~(-1)), implying a substantial effect of the Ta-based support films.