Iron-Decorated Nitrogen/Boron co-Doped Reduced Graphene Oxide Aerogel for Neutral Rechargeable Zn-Air Batteries

Abstract

Zn-air batteries (ZABs) with neutral electrolytes offer a significantly longer lifespan and better recyclability than alkaline ones. However, low-performance bifunctional catalytic activities for oxygen reduction or evolution reaction (i.e., ORR/OER) in neutral electrolytes still hamper their development. Here, we report iron nanoparticle-decorated nitrogen/boron co-doped reduced graphene oxide aerogel (Fe-NBrGO) with distinguished ORR/OER activity, enabling its application in neutral rechargeable ZABs. Taking advantage of the formation of 3D porous structure of graphene aerogel, N/B-moieties active sites, and Fe-containing active sites, Fe-NBrGO exhibits high ORR onset potential (1.074 and 0.817 V) and adequate OER overpotential (476 and 615 mV) in alkaline and neutral electrolytes, respectively. Fe-NBrGO enables the production of a neutral-ZAB with 34 mW cm−2 in peak power density and remains stable for a 284 h (~852 cycles) cycling test. This research highlights the rational design of highly active oxygen catalysts for the widespread implementation of new energy storage technologies.

Recent advances in the functionalization, substitutional doping and applications of graphene/graphene composite nanomaterials

“…The insertion of N/B moieties can create active sites for transition metals that can exhibit high ORR in the whole system. Y. Irmawati et al 117 reported a typically designed nanocomposite of iron-decorated N/B co-doped reduced graphene oxide (rGO-NB/Fe) as an electro-catalyst for ORR and OER systems, acting as alkaline and neutral electrolytes, respectively and creating active sites that can modify the electronic structure of rGO in the system. Thus, its applicability (3D porous structure) as graphene aerogels with N/B moieties, with Fe-decorated nanocomposite, for a highly stable Zn–Air battery (34 mW cm −2 in power density and remaining stable for 284 h; ∼852 cycles) was acclaimed.…”

Trifunctional electrocatalysts based on a bimetallic nanoalloy and nitrogen-doped carbon with brush-like heterostructure

“…Nonprecious transition metal–nitrogen–carbon materials have been well-explored as promising candidates for ORR/OER/HER catalysts. 9–12 Among the nonprecious transition metals, Co-based catalysts are stated to be near the peak of OER/HER volcano plots, indicating their highly efficient and competitive OER/HER activity. 13,14 Meanwhile, although Fe-based catalysts exhibit relatively low OER/HER activities, they are considered to be some of the best substitutes for Pt-based catalysts owing to their high ORR activity.…”