Electrolyte effects on electrochemical properties of osmium complex polymer modified electrodes

The electrolyte effects on the electrochemical behaviors of osmium complex polymer modified electrodes were investigated by a comparison between two o smium complexes, [Os(bpy)(2)(PVI)(10)Cl]Cl (Os-PVI10) and [Os(bpy)(2)(PVP)( 10)Cl]Cl (Os-PVP10). The electrode process at Os-PVI10 modified electrodes is reaction-controlled. while a diffusion-controlled electrode process exis ts at Os-PVP10 modified electrodes. Both the cation and anion in supporting electrolytes strongly affect their electrochemical behaviors, such as the redox potential, wave shape and peak current. These phenomena are attribute d to a change in the film structure and polymer swelling in various support ing electrolytes. The influence of electrolyte anions on the electrochemica l behaviors is related to their hydrophobicity. The electrode process of Os -PVP10 depends on the pH Value of solutions, exhibiting different electron transfer mechanisms.