Mo-x(CO)(n) and MoxSy(CO)(n) ectrocatalysts were synthesized following a sintering process in air at 150 degreesC. The catalysts were characterized using techniques such as X-ray diffraction(XRD), scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR) and cyclic as well as linear voltametry measurements. The results indicated that sintered Mo-x(CO)(n) possesses catalytic activity for oxygen reduction reaction. Incorporation of sulfur to the carbonyl compound seems to nullify the catalytic activity of the material. These materials are porous in nature and formed in amorphous form or with poor crystallinity. The voltammograms indicated its possible application in supercapacitor electrodes and for hydrogen evolution reaction. (C) 2000 International Association for Hydrogen Energy. Published by Elsevier Science Ltd. All rights reserved.