Plots (Figure 9) present values of ΔI of all obtained systems as a function of temperature. Matching these values with a predominant chemical form of platinum at a given temperature that results from subsequent stages of the metal precursor decomposition [36] allows to one draw conclusion regarding its most active form in electrochemical processes. This studies lead to conclusion that hydrated hexachloroplatinic acid (H2PtCl6 · 6H2O) is not active in electrochemical processes. The activity of all system increases rapidly after removal of the coordinating water (Eq. 2). It is the most prominent for high platinum content systems. Plots and collected data show that oxidation state of Pt is a determining factor of its activity and for systems in which platinum is at II or IV oxidation state [32].