Design of Fe and Cu bimetallic integration into nitrogen-containing microporous graphene-like carbon via a hard-template-assisted strategy as an oxygen reduction catalyst for Al–air batteries

Abstract

The performance of the oxygen reduction reaction (ORR) can be enhanced through the utilization of multi-heteroatom doped, porous, and layered electrocatalysts. Nitrogen-doped graphene-like porous carbon (Cu–Fe–CN) was synthesized via a simple and cost-effective NaCl template method using maltose, FeCl₃·6H₂O, and CuCl₂·H₂O as precursors. This material exhibits excellent electrocatalytic activity towards the ORR. During the electrocatalysis process, the maltose-derived graphene-like porous carbon possesses abundant pores that facilitate rapid mass and electron transfer. Additionally, the incorporation of polyatomic dopants and the construction of the porous carbon framework result in an abundance of active sites. The optimized Cu–Fe–CN electrocatalyst exhibited a more positive half-wave potential (E_1/2 = 0.87 V) in alkaline media, surpassing that of the commercial Pt/C (E_1/2 = 0.84 V), and demonstrated exceptional durability. The average discharge voltage of Al–air batteries with the Cu–Fe–CN catalyst is always higher than that of Al–air batteries with the commercial Pt/C catalyst, at the same current density. The present study showcases a convenient approach for fabricating porous low-metal catalysts for the ORR, highlighting their immense potential in ORR catalysis and aluminum–air batteries.