(FeCo/Ppy@C): Pt-free FeCo-Polypyrrole Nanocomposites Supported on Porous Carbon for Electrochemical Application

The synthesis and characterization of pyrolyzed carbon-supported transition metal/nitrogen (M–Nx/C) material based on FeCo alloy and Polypirrol as source of N atoms are presented. Two different synthetic protocols, a multi-step and a novel one pot single-step approach are compared. In both approaches two different Fe:Co ratio (50:50 and 75:25) were used to obtain Pt-free FeCo-Polypyrrole nanocomposites supported on porous carbon (FeCo/Ppy@C). Structural and morphological characterizations of the samples before and after pyrolysis were carried out by using X-Ray Powder Diffracion, Infrared Spectroscopy and High-Resolution Transmission Electron Microscopy. For both approaches, nanoparticles with a core shell structure but different size and matrix polidispersivity were observed after pyrolysis when a Fe:Co 50:50 ratio was used. Bigger nanoparticles were obtained after pyrolysis in the 75:25 ratio samples, with no significant differences between the two approaches. The electrocatalytical properties of the final samples, investigated by cyclic voltammetry in an acidic electrolyte, showed the presence of a cathodic current density.