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A bimetallic catalyst improves the physical and chemical properties of a bimetal because of an increased synergistic effect of the two different metals compared with those of their corresponding single particles. Therefore, in this study, a bimetal consisting of iron and cobalt (FeCo) supported with nitrogen-doped reduced graphene oxide (FeCo/NG) was successfully synthesised as a potential catalyst using a thermal annealing method for the oxygen reduction reaction (ORR). Dicyandiamide was used as the N precursor. Thermal annealing was performed at a high temperature (600 degrees C-800 degrees C) using transition metal precursors of FeCl3 and Co(NO3)(2)center dot 6H(2)O with different Fe/Co molar ratios. The morphology analysis by means of field emission scanning electron microscopy (FESEM) and transmission electron microscopy (TEM) showed that the average size of the FeCo nanoparticles is between 20 nm and 130 nm. With increasing annealing temperature, the size of the nanoparticles drastically grew, and they were well dispersed on the NG surface. XPS analysis revealed that the pyridinic-N configuration had the highest percentage of 62.61% compared to that of the others. This configuration acted as the active site for the enhanced ORR in an alkaline medium. The catalyst with a 1:2 molar ratio synthesised at 700 degrees C (1:2FeCo/NG700) exhibited the highest performance in 0.1 M KOH medium with a comparable potential of 0.74 V vs. RHE compared to those of the other catalysts. It exhibited a higher current density of 0.605 mA cm(-2) compared with that of commercial Pt/C (0.75 V vs. RHE, 0.569 mA cm(-2)). Based on linear sweep voltammetry (LSV) analysis, the average number of electron transfers (n) of 1:2FeCo/NG700 was between 3.60 and 3.99 in the potential range of 0.0-1.0 V vs. RHE; this revealed that the 1:2FeCo/NG700 catalyst undergoes 4-electron pathways. These findings show that FeCo/NG is an active catalyst towards ORR in an alkaline medium, thereby justifying i

Nowadays the world concern about the alternative solutions to the combustion engine due to the problem of the decreasing resources of crude oil and its recent environmental impact. One of the attention that are paid by most of the automotive industries is proton exchange membrane fuel cell (PEMFC). To comply with the modern automobiles a fast and highly responsive supply of hydrogen with no byproduct other than carbon dioxide must be found. The high selectivity requirement emanate from the sensitivity of the PEM containing Pt as the catalyst for proton exchange.

Nowadays the world concern about the alternative solutions to the combustion engine due to the problem of the decreasing resources of crude oil and its recent environmental impact. One of the attention that are paid by most of the automotive industries is proton exchange membrane fuel cell (PEMFC). To comply with the modern automobiles a fast and highly responsive supply of hydrogen with no byproduct other than carbon dioxide must be found. The high selectivity requirement emanate from the sensitivity of the PEM containing Pt as the catalyst for proton exchange.