CLAY-MODIFIED ELECTRODES PREPARED BY THE LANGMUIR-BLODGETT METHOD

An ion-exchange adduct of saponite with tetra-n-decylammonium cation ( (n-decyl)(4)N+) was prepared and dispersed in chloroform. The material was spread on a water surface to form a thin film at the air-water in terface. From the measurements of surface pressure vs. area, it was co ncluded that the film consisted of the very thin layer which was a mix ture of single and double layers of saponite adduct. A clay-modified e lectrode was prepared by depositing the film on a glassy carbon substr ate using the Langmuir-Blodgett method. When the electrode was soaked in an aqueous solution of [Fe(phen)(3)](ClO4)(2) (phen = 1,10-phenanth roline), (n-decyl)(4)N+ cations were replaced by [Fe(phen)(3)](2+) ion s from solution. This process was followed by measuring the cyclic vol tammogram.