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The electrocatalytic activity of mixed Ru-Ir oxide electrodes fabricated by thermal decomposition are compared (using cyclic voltammetry and potentiodynamic technique), for their ability to evolve hydrogen and oxygen in both 1N H2SO4 and 1N NaOH solutions. Cyclic voltammetry provides information about the redox transitions of surface oxyruthenium and oxyiridium groups, and also generates an effective index, (voltammetric charge (q*)), which can be used to determine the electrocatalytic activity of the electrode. In this study, q* (obtained by numerical integration from CV), indicates that maximum activity results from a coating solution with 60 to 80 mol % Ir content. It is noted that, for acidic solutions, voltammetric charge in the region of hydrogen adsorption]desorption, (qn), exhibits the same trends as q*. The potentiodynamic technique, on the other hand, is employed to yield Tafel plots providing log(i) vs. E relations. It is found that the activity of RuO2 is worst for oxygen evolution in alkaline solutions, while its electrochemical behavior for hydrogen evolution is the same for both acidic and basic solutions. In contrast, it is found that the electrochemical behavior of IrO2 for hydrogen evolution is significantly influenced by pH.

Polyaddition of isophorone diisocyanate to poly(oxypropylene)glycol (PPG)-Based waterborne polyurethane (WPU) synthesized by a modified acetone process was performed. Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), differential scanning calorimetry (DSC), and impedance spectroscopy (IS) were utilized to monitor the phase change of this WPU with the doped lithium perchlorate (LiClO4) concentration. Significant changes occur in the FTIR spectrum of the WPU with the added salt concentration above 1 mmol/g WPU, indicating that an interaction with the lithium cation within the hard segment and between the hard and soft phases occurs. The soft segment T g increases with increasing LiClO4 through the examination of DSC. XPS results reveal that the component of nitrogen polaron sites (N+) increases with increasing LiClO4 and that the saturation level of salt doping is evidenced by the mole ratio of component C−O to CO; meanwhile, a rearrangement in the long chain of the soft domain has also been observed when this WPU is doped with LiClO4. IS results indicate an increase in bulk conductivity as the salt concentration is increased.