The octyltrimethylamonium bromide adsorption at the electrode/NaClO4 solution interface

Abstract

The behaviour of octyltrimethylammonium bromide electrosorption on the mercury electrode in 1 M NaClO₄ was determined by means of double layer differential capacity measurements. The adsorption constants were derived from pressure data as a function of electrode charge density and cationic surfactant bulk concentration. Adsorption of octyltrimethylammonium bromide was analyzed using constants obtained from Frumkin, corrected Flory-Huggins and virial isotherms. The study found that the repulsive interactions for electrode charges close to 0 were the weakest between the adsorbed cations C₁₁H₂₆N⁺. In these conditions the surface concentration of the studied surfactant was the greatest.