Dysprosium-induced FeNx-Dy2O3 sites for Efficient Bifunctional Oxygen Electrocatalytic Reactions

Abstract Iron and nitrogen co-doped carbon material (Fe/NC) is considered as a promising catalyst for oxygen reduction reaction (ORR) due to its excellent catalytic activity. However, it is still challenging to further reform the activity of ORR and oxygen evolution reaction (OER). Rare earth elements with unique orbital configuration and catalytic behavior are widely regarded as effective promoters to enhance the electrocatalytic activity of materials. Here, we successfully optimized the oxygen electrocatalytic activity of Fe/NC by the novel addition of Dy element, denoted as Dy 2 O 3 -Fe/NC. The resulting material shows excellent ORR/OER activity in 0.1 M KOH, with a half-potential (E 1/2 ) of 0.914 V and an overpotential of 396 mV (at a current density of 10 mA cm -2 ). The excellent bifunctional electrocatalytic activity is derived from the close synergistic interaction between Fe and Dy, as well as the newly generated active sites of FeN x -Dy 2 O 3 . Zn-air battery assembled with Dy 2 O 3 -Fe/NC as cathode catalyst shows a high peak power density (225 mW cm -2 ) and long-term charge-discharge cycle stability.