VOLTAMMETRIC BEHAVIORS OF CHEMICALLY-MODIFIED ELECTRODES BASED ON ZIRCONIUM PHOSPHONATE FILM

Electroactive monolayers based on zirconium(IV) phosphonate film were prepared on gold and tin oxide electrodes by sequential layer-by-layer depostion technique. High transfer coefficient values and surface cov erages of surface bound redox molecules were obtained from the electro chemical measurements of heterogeneous electron transfer rates for mon olayer modified electrodes. 1,10-Decanediylbis(phosphonic acid) (DBPA) monolayer as insulating barrier was effective in blocking electron tr ansfer. However, these film modified oxide electrode shows voltammetri c behavior of diffusion/permeation process taking place at very small exposed area of modified electrode through channels due to structural defects within film when a very fast redox couple such as Ru(NH3)(6)(3 +) is hired.