Enhancing oxygen reduction reaction of Pt–Co/C nanocatalysts via synergetic effect between Pt and Co prepared by one-pot synthesis

Designing highly active and durable electrocatalysts towards oxygen reduction reaction (ORR) plays a paramount importance for proton exchange membrane fuel cells. Pt-based binary alloys Pt-M (M = 3d-transition metals) possessing excellent electronic and geometric properties have received increasing interests as highly active electrocatalysts. Herein, we report a series of Pt x Co/C ( x  = 1, 2, 3) catalysts by a facile one-pot soft-chemistry method. In the acidic conditions, the mass activities of PtCo/C, Pt 2 Co/C and Pt 3 Co/C are 0.526, 0.462 and 0.441 A·mg Pt −1 , which are 2.60, 2.31 and 2.22 times higher than that of Pt/C (0.200 A·mg Pt −1 ), respectively. The specific activities of PtCo/C, Pt 2 Co/C and Pt 3 Co/C are 706.59, 679.41 and 801.83 μA·cm −2 , which are accordingly 2.89, 2.76 and 3.28 times higher than that of Pt/C (244.75 μA·cm −2 ). Notably, Pt 3 Co/C shows a remarkable durability. After 5000 cycles of the accelerated durability testing, the mass activity and specific activity of Pt 3 Co/C catalyst are 2.47 and 3.80 times higher than that of the commercial Pt/C, respectively. The improved ORR activity and durability can be ascribed to the synergistic interaction between Pt and Co. Graphical