NOVEL LOW-TEMPERATURE SYNTHESIS OF SEMICONDUCTING TRANSITION-METAL CHALCOGENIDE ELECTROCATALYST FOR MULTIELECTRON CHARGE-TRANSFER - MOLECULAR-OXYGEN REDUCTION

Powder and thin layers (<0.5 mu m) of transition metal chalcogenide de posited on various substrates (glass, gc, ito) were synthesized at 140 degrees C. The catalyst compound was obtained when reacting the corre sponding transition metal carbonyl compounds and elemental selenium in xylene solvent. Efficient reduction of molecular oxygen to water, in 0.5 M H2SO4 electrolyte, was obtained. This catalyst also showed semic onducting behaviour. XPS-analysis and those results gained by Rutherfo rd backscattering spectrometry (RBS) revealed that oxygen is incorpora ted in this compound. Transmission electron microscopy (TEM) performed on thin layers deposited on conducting glass or glassy carbon electro des consisted of amorphous regions and nanocrystal domains with partic le sizes ranging from 30 to 40 Angstrom. The probable stoichiometry of the semiconducting catalyst compound resulted to be: (Ru1-xMox)(y)SeO z where 0.02 < x < 0.04; 1 < y < 3 and z approximate to 2y after data analysis obtained with XPS, RBS and TEM.