The partitioning of surfactants from the gas-solution interface onto an electrified metal-solution interface

Abstract

The spreading of long-chained aliphatic molecules from the gas-solution interface to an electrified gold-solution interface was studied. Three low index planes of gold were used as the electrodes and the film pressure at the metal-solution interface was determined by electrochemical means under equilibrium conditions. The spreading of the molecules from the gas-solution interface to the metal-solution interface was measured and a strong dependence on electrode potential and electrode surface morphology was found. Stressed (compressed) and unstressed (not compressed) monolayers were studied and compared. The stressed monolayer study suggested that the equilibrium for the spreading of molecules between the gas-solution interface and metal-solution interface may be local in character.