Low Pt loading amorphous alloys applied as anodes and the effect of different proton exchange membranes for PEMFCS

• Amorphous bi-metallic Ni59Nb40Pt0.6X0.4 (X = Ru, Sn) alloys were studied as anodes in PEMFCs.
• Electro-catalysts were obtained by mechanical alloying.
• The chosen membranes to be studied were Nafion® 117, Nafion® 115 and Nafion® XL.
• Two different fuel cell surfaces were used: 9 cm2 and 25 cm2.

In this work low-loaded platinum bi-metallic amorphous alloys based on Ni59Nb40Pt0.6X0.4 (X = Ru, Sn) were studied as electro-catalytic anodes in PEMFCs. The electro-catalysts were produced by Mechanical Alloying (MA) using a planetary ball-mill during 40 h and used as anodes onto Nafion® (DuPont) perfluorinated membranes (Nafion® 117, Nafion® 115 and Nafion® XL). In addition, two active areas of fuel cells were used namely 9 and 25 cm2. These electro-catalysts were characterized by both physical and chemical techniques, such as Differential Scanning Calorimetry (DSC), X-ray Diffraction (XRD) and Energy Dispersive X-ray Spectroscopy (EDX). Concerning the performance towards the Hydrogen Oxidation Reaction (HOR), the results showed that 25 cm2 of active area of fuel cell with Ni59Nb40Pt0.6Ru0.4 alloy and the Membrane Electrode Assembly (MEA) based on the Nafion® 115 membrane exhibited the best catalytic activity (2083.59 A g−1 Pt), while for the Ni59Nb40Pt0.6Sn0.4 catalyst the Nafion® XL membrane was more suitable (1570.82 A g−1 Pt).