Single-site and nanosized Fe–Co electrocatalysts for oxygen reduction: Synthesis, characterization and catalytic performance

摘要: Abstract The impregnation of Ketjen Black (C) with iron and cobalt phthalocyanines ( MPc ) taken one by or as a 1:1 stoichiometric mixture, followed heat treatment at 600 °C under inert atmosphere, gave materials containing arrays single metal ions coordinated four nitrogen atoms (M-N 4 units). Increasing the pyrolysis temperature to 800° resulted in formation carbon-supported, nanosized particles. A key role carbon support determining material structure either investigated was demonstrated TPD, EXAFS, XANES XRPD studies. These also showed that Fe–Co alloy is obtained 800 °C when involves mixture FePc CoPc . Electrodes coated different Fe, Co materials, ca. 3 wt% loadings, were scrutinized for oxygen reduction reaction (ORR) alkaline media linear sweep voltammetry. For comparative purposes, two Pt electrocatalysts 3 20 wt% investigated. electrochemical activity all analyzed Tafel Koutecky–Levich plots well chronopotentiometry. Fe-containing have been found be highly active ORR convective limiting currents high 600 A g Fe −1 room onset potentials 1.02 V vs. RHE. It has (i) mass Pc -derived superior catalysts investigated; (ii) FePc–CoPc/C , treated 600 800 °C, corresponding materials; (iii) are fairly more than those 800 °C.