Influence of thermal treatment on RuSe cathode materials for direct methanol fuel cells

The effect of thermal treatment on the activity of the carbon-supported ruthenium and selenium cathode catalysts for the oxygen reduction reaction is evaluated in both half-cells and in fuel cells, using voltammetric and steady-state polarisation techniques. The catalysts treated at 300 and 400 degrees C give a better performance compared to that of the as prepared samples. The catalysts are characterised by scanning electron microscopy, energy-dispersive X-ray spectrometry, and X-ray diffractometry in terms of the crystalline state, morphology, and composition of the materials. The formation of porous RuSe binary interfaces and the transformation from the amorphous to crystalline state are directly linked to the heat treatment temperatures, which in turn, affect the activity and methanol tolerance of the catalysts. The RuSe/C is compared to Pt/C cathode materials.