Binary FeCo-N-doped carbon/carbon nanotube composites for efficient oxygen reduction and high-performance aluminum-air battery

Abstract

Aluminum-air batteries (AAB) have been expected as one promising energy technology for next-generation electrical vehicles owing to their low costs, light weights, high specific energy, environmental benignity and mechanical rechargeability. Yet currently, efficient catalytic materials for air cathodes are mostly based on expensive and scarce precious metal Pt, which have severely impeded the implantation of AAB. Herein, a series of non-precious binary FeCo-nitrogen-doped carbon (FeCo-NC) materials with heavily loaded Fe/Co species and in-situ generated interconnected carbon nanotube (CNT) were synthesized from cost-effective materials. With merits of dense active sites, largely exposed surface area, and good electron/ionic conductivity, the as-made binary FeCo-NC with optimal synthetic parameters exhibit excellent oxygen reduction reaction performance in alkaline electrolyte, rendering high onset potential of 1.05 V and half-wave potential of 0.91 V, which surpass those of Pt/C by 50 and 40 mV, respectively. Remarkably, the FeCo-NC-assembled AAB delivers an exceptional open-circuit voltage of 1.88 V and a large specific power of 188 mW cm−2, and additionally maintains high discharge voltage of 1.70 V at the current density of 10.0 mA cm−2. Our work renders a new type of high-performance air cathode material for AAB implantation.