Ruthenium monometallic electrocatalysts for the hydrogen oxidation reaction (HOR) were prepared by microwave irradiation in o-dichlorobenzene and ethylene glycol. The products were characterized structurally by X-ray diffraction and FT-IR spectroscopy; morphologically by scanning electron microscopy and their chemical composition was determined by energy-dispersive spectroscopy analysis. The electrocatalytic properties of the materials were evaluated by rotating disk electrode measurements in 0.5 mol L-1 H2SO4. The kinetic parameters, such as the Tafel slope, exchange current density and charge transfer coefficient, are reported. The ruthenium electrocatalysts show a dual-path mechanism in a similar way as platinum. (C) 2013 Elsevier B.V. All rights reserved.