Effect of Ni loading onto Pt (Pt-Ni/C) electrocatalysts for PEM fuel cell: A study of ORR activity, stability, and temperature effect

Abstract

Pt is a noble metal when alloyed with transition metals like Ni onto the carbon support, minimizes the cost and increases the oxygen reduction reaction (ORR) activity and stability of Pt-Ni/C electrocatalyst in a low-temperature proton exchange membrane (LTPEM) fuel cell. A simple sonochemical-based synthesis of Pt-Ni/C bimetallic nanoparticles is carried out through varying amounts of Ni and Pt precursors. The various combinations of Pt and Ni metal (50:50, 75:25, and 83:17) nanoparticles were uniformly distributed on a carbon support. The shifting of 2θ values to higher levels in XRD patterns confirmed the alloy formation between Pt and Ni. The carbon (60 wt. %) supported Pt and Ni (40 wt. %) electrocatalyst ink is coated on a carbon paper which acts as a gas diffusion layer (GDL). The electrocatalytic performance of Pt-Ni/C was evaluated in the PEM fuel cell using an electrochemical test station. The best performance was observed with the Pt: Ni (83:17) coated electrocatalyst, which delivered 0.162 W/cm² power at 0.45 V. Also, the PEM fuel cell performance was enhanced by increasing the single cell's operating temperature.