Synthesis and characterization of W 0.12Ru 2.1Se and W 0.013Ru 1.27Se electrocatalysts

Abstract

Nanosized particles of cathodic electrocatalysts were chemically synthesized by reacting transition metal carbonyl compounds and elemental selenium in m-xylene (bp 402 K) and o-dichlorobenzene (bp 443 K). The characterizations of the synthesized materials were performed by neutron activation analysis (NAA), scanning electron microscopy (SEM), high resolution transmission electron microscopy (HRTEM), and infrared spectroscopy (IR). The resulting chemical composition was W 0.12Ru 2.1Se and W 0.013Ru 1.27Se for the compounds synthesized in m-xylene and o-dichlorobenzene, respectively. X-ray diffraction spectra (XRD) showed in both cases the formation of amorphous materials and SEM micrographs depict primary particles with almost the same granular morphology. TEM micrographs showed that the particles synthesized in m-xylene were amorphous, dispersed particles and in o-dichlorobenzene were amorphous nanocluster materials of approximately 2 nm in size. The growth of the nanoclusters depends only on the synthesis temperature and not on the nature of the solvents. The synthesized electrocatalysts showed catalytic activity for the molecular oxygen reduction in 0.5 M H 2SO 4 and could be candidates to be used as cathodes for fuel cells.