Porous Pt-Ni Nanobelt Arrays with Superior Performance in H₂/Air Atmosphere for Proton Exchange Membrane Fuel Cells

To reduce cost and energy consumption of fuel cell vehicles, constructing membrane electrode assemblies (MEAs) with low Pt loading and outstanding performance at low relative humidity (RH) conditions is reported. A catalyst layer based on porous Pt–Ni nanobelt arrays was prepared, in which the strained catalyst enhanced the catalytic activity and the oriented nanobelt array structure provided convenient mass transport channels. The porous Pt–Ni nanobelt arrays were prepared by the magnetron sputtering of Pt and Ni on a sacrificed template and then washed with acid. Consequently, the catalyst layer based on the porous Pt–Ni nanobelt arrays exhibited superior fuel cell performance in H2/air conditions and RH 40%. The performance of the MEA with porous Pt–Ni nanobelt arrays reach 366.6 and 597.6 mW cm–2 with Pt loadings of 36.5 μg cm–2/36.5 μg cm–2 and 108.9 μg cm–2/108.9 μg cm–2 at the cathode/anode, respectively. A conventional CCM with the Pt loading of 100 μg cm–2/200 μg cm–2 at the cathode/anode served as the benchmark, and the cell performance was 230.5 mW cm–2. Apart from that, the Pt nanobelt arrays without a porous structure (100.8 g cmPt–2/100.8 μg cmPt–2) serving as another benchmark achieved a performance of 504.7 mW cm–2. The superior performance of the porous Pt–Ni nanobelt arrays is attributed to the convenient mass transport pathway and the high activity of the porous Pt–Ni nanobelt.