Platinum was incorporated into the cavities of NaX zeolite by impregration/thermal decomposition technique, using Pt(II)-acetylacetonate in acetone as an impregnating solution. The platinum-to-zeolite weight ratio amounted to 0.092. The sample was characterized by thermogravimetry, X-ray diffraction and Na-23 MAS NMR methods. The mixture of modified zeolite and 10 wt. % of carbon black, in a form of thin layer, was pasted to a glassy carbon stance. With such an electrode material, the electrochemical decomposition of aqueous 2.5 mM H2SO4 + 1 M Na2SO4 solution with hydrogen and oxygen production has been kinetically studied. In comparison with smooth polycrystalline platinum, this electrode material provided an remarkable overvoltage drop,for water splitting, primarily due to the acceleration of oxygen evolution reaction
