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 interface. From the measurements of surface pressure vs. area, it was concluded that the film consisted of the very thin layer which was a mixture of single and double layers of saponite adduct. A clay-modified electrode was prepared by depositing the film on a glassy carbon substrate using the Langmuir-Blodgett method. When the electrode was soaked in an aqueous solution of [Fe(phen)(3)](ClO4)(2) (phen = 1,10-phenanthroline), (n-decyl)(4)N+ cations were replaced by [Fe(phen)(3)](2+) ions from solution. This process was followed by measuring the cyclic voltammogram.