A novel Fe/N/C electrocatalyst prepared from a carbon-supported iron(ii) complex of macrocyclic ligands for oxygen reduction reaction

Abstract

Herein, we report a novel method to synthesize Fe/N/C composites from a carbon-supported iron (II) coordination complex of 2,3-dicyanotetraazabenzotriphenylene (2,3-DCTBT) ligands towards oxygen reduction reaction (ORR) in alkaline media. We investigated the influence of different temperatures during the thermal carbonization process on the performance of the catalyst, and Fe/N/C-900 stood out among all other samples because of the existence of Fe–N_x active sites. The as-obtained Fe/N/C-900 exhibited excellent electrochemical performance (E_onset is 0.98 V vs. RHE in 0.1 M KOH) for the oxygen reduction reaction (ORR) compared with the commercial 20% Pt/C. Moreover, this catalyst possessed good stability and high tolerance to methanol, and followed the four-electron mechanism (n = 3.97). Remarkably, the use of 2,3-DCTBT for the first time as a precursor has opened new avenues to prepare electrocatalysts for ORR.