Monoatomic Fe and Pt-Co alloys on NC/Ti4O7 for efficient and durable oxygen reduction

Abstract

The combination of metal monoatomic with alloys on carbon support facilitates the promising activity in oxygen reduction. However, the alloys still suffer from the degradation of catalyst stability due to carbon corrosion. Herein, the NC/Ti4O7 support was loaded with both monoatomic Fe and Pt-Co alloys using a one-step calcination method. The results indicate that chelation of Fe3+ with α-D-glucose, physical segregation of excess α-D-glucose and binding to N species at high temperatures are essential to increase the loading of monatomic Fe in Fe1/PtCo-NC/Ti4O7. Fe1/PtCo-NC/Ti4O7 demonstrates a half-wave potential of 0.941 V and a mass activity of 3.16 A mgPt -1. This mass activity is as high as 6.87 times that of Fe/PtCo-NC/Ti4O7 (without α-D-glucose during the synthesis, 0.46 A mgPt -1). Meanwhile, Fe1/PtCo-NC/Ti4O7 exhibits a peak power density of 210.5 mW cm-2 and a specific capacity of 771.1 mAh gZn -1 in a zinc-air battery. This dual-substrate strategy provides a new perspective on the multilevel construction of catalysts.