Carbon particles co-doped with N, B and Fe from metal-organic supramolecular polymers for boosted oxygen reduction performance

Abstract

Rational design of high-efficiency and cost-effective nonprecious metal-based catalysts with outstanding oxygen reduction reaction (ORR) performance, is of great importance to replace platinum-based electrocatalysts in fuel cell. Herein, a novel N, B and Fe co-doped carbon materials (Fe-NBC) electrocatalyst is designed through the pyrolysis of a metal-organic coordination polymer precursor, which is formed from the coordination between dendrimer-like terpyridinic monomer and Fe3+. The as-prepared Fe-NBC catalyst exhibits superior ORR activity with an onset potential of 0.98 V and a half-wave potential of 0.86 V, which are comparable to that of the Pt/C catalyst. The formation of Fe-Nx moieties is considered to be the most important factor for the improved ORR activity of Fe-NBC. Besides, Fe-NBC catalyst displays a better methanol tolerance as well as durability (5 mV negative shift of E1/2, after 1000 cycles) in comparison with Pt/C (12 mV negative shift of E1/2, after 1000 cycles). This work provides a facile protocol for the design and fabrication of multi-element co-doped carbon materials. Moreover, the excellent ORR performance of these N, B and Fe co-doped carbon materials may be a potential candidate to replace Pt-based catalyst in fuel cells.