Montmorillonite as a catalytic support in water electrolysis

The paper presents a research on the phyllosilicate mineral Montmorillonite (MMT) in regard to its properties as catalytic support for hydrogen generation via electrochemical water splitting. MMT is loaded with noble metal nanoparticles (Ir) having well proven high catalytic activity toward the oxygen evolution reaction (OER). The metal is deposited by the well-established sol gel technique. The catalytic loading is varied in the range 10-30 wt. %. The obtained montmorillonite-supported catalysts (Ir/MMT) are studied using X-ray diffraction (XRD), scanning electron microscopy (SEM), and energy dispersion X-ray (EDX) analysis. Their electrochemical performance and OER catalytic efficiency are investigated by cyclic voltammetry and quasi steady state polarization curves in aqueous acid solution. The performed morphological and electrochemical investigations showed that the Ir/MMT catalysts under study possess superior performance in regard to both activity and durability compared to the previously studied iridium catalysts supported on commercial electrically conductive ceramic support Magnelli phase titania.