Single-atom lanthanum on 2D N-doped graphene oxide as a novel bifunctional electrocatalyst for rechargeable zinc-air battery

Conventional carbon materials have poor electrocatalytic performance due to few active sites. Herein, a rare-earth lanthanum (La) is introduced into the N-doped graphene oxide (NGO) to form the single-atom 2D La@NGO. We analyze the properties of La@NGO series and find that 7%La@NGO shows the most excellent oxygen reduction reaction performances with a half-wave potential up to 0.86 V, outstanding stability, and methanol tolerance in 0.1 M KOH, which are all superior to those of commercial Pt/C electrocatalyst. In addition, 7%La@NGO shows good bifunctional electrocatalytic behaviors with a low Delta E of 0.72 V. The rechargeable zinc-air battery assembled by 7%La@NGO possesses a high power density of 80.9 mW/cm(2), a large specific capacity of 640 mAh/g, a high rechargeable efficiency of 55.2%, as excellent cycling stability. (C) 2022 Elsevier Ltd. All rights reserved.

Automated summary

In this study, a rare-earth lanthanum (La) was introduced into N-doped graphene oxide (NGO) to form the single-atom 2D La@NGO, which exhibited excellent oxygen reduction reaction performances and methanol tolerance. The 7%La@NGO showed the best performance among the La@NGO series, surpassing the commercial Pt/C electrocatalyst, and also exhibited good bifunctional electrocatalytic behaviors. The rechargeable zinc-air battery assembled with 7%La@NGO demonstrated high power density, large specific capacity, high rechargeable efficiency, and excellent cycling stability.