Cathodic adsorption voltammetry of palladium(II)

The electrochemical behavior of palladium(II) was studied by differential p ulse, linear sweep, and alternating-current square-wave voltammetry in HCl, HNO3, H2SO4, and HClO4 solutions in the presence of dimethylglyoxime. A pe ak with a height linearly depending on the concentration of palladium(II) w as observed in voltammograms. Typical relationships between the height and potential of a peak and pH, dimethylglyoxime concentration, the potential a nd time of adsorption accumulation suggested that the observed peak was due to the hydrogen liberation catalyzed by palladium(II) dimethylglyoximate a dsorbed on the electrode surface. The detection limits for palladium(II) ac cumulated for 120 s at -0.2 V were 2 x 10(-8), 5 x 10(-9), and 8 x 10(-10) M for differential pulse, linear sweep, and alternating-current square-wave voltammetry, respectively.