Highly stable PtCu3Auy nanowires-nanoparticles composite as efficient electrocatalysts towards oxygen reduction reaction

Developing platinum-based catalyst with low-platinum content and efficient oxygen reduction reaction (ORR) is critical to expediting the industrialization of fuel cells. Platinum-based alloy nanowires are widely applied as ORR catalyst but limited by poor stability and high platinum consumption. Herein, platinum-copper(3)-gold(y) nanowires-nanoparticles composite (PtCu3Auy NWP, y = 0.2, 0.5 and 0.8) is smoothly synthesized by solvothermal and in-situ reaction diffusion. The mass activity (MA) of PtCu3Au0.5 NWP/C reaches 1.422 A mg(Pt&Au)(-1) (with an ultralow Pt&Au loading of around 6.43 wt%) which is 13.16 times higher than commercial Pt/C. The excellent ORR catalytic activity of PtCu3Au0.5 NWP is attributable to its structure of nanowires-nanoparticles, strong ligand effect and proper lattice strain. The MA of PtCu3Au0.5 NWP only decreases by 13.2% while Pt/C decreases by 52.8% after 10,000 cycles of the accelerated durability testing (ADT). Moreover, the PtCu3Au0.5 NWP catalyst exhibits only 7.88% loss of maximum power density after 10,000 ADTs in single-cell test. Such an excellent stability for PtCu3Au0.5 NWP can be ascribed to the structure of nanowires-nanoparticles composite and Au-rich layer on the surface. This research uncovers a practical method for improving the stability and activity of nanowires made from platinum-based alloy.