Ultra-Thin Ptfe-Nanowires As Durable Electrocatalysts for Oxygen Reduction Reaction

Abstract: The sluggish cathode reaction rate and poor catalyst durability are two main hurdles that hamper the large-scale application of proton exchange membrane fuel cells (PEMFCs). Recently, we prepared an ultra-thin Pt_xFe_y-nanowire (NW) catalyst with a diameter (2 – 3 nm) and a large surface area (52 m²/g), through a solution-phase reduction method. The Pt_xFe_y-NW catalyst demonstrated a higher oxygen reduction reaction (ORR) activity and better electrochemical durability than conventional Pt/C catalyst in a three-compartment-cell test. After 1000 cycles of 0 – 1.3 V (vs. RHE) accelerated durability test, the relative electrochemical surface area (ECSA) of Pt₂Fe₁-NW drops down to 46%, which is two times better than commercial Pt/C catalyst. In addition, the mass activity at 0.85 V (vs. RHE) on Pt₁Fe₁-NW is 39.9 mA/mg_Pt after durability test, which is twice that of Pt/C catalyst(18.6 mA/mg_Pt).