QCM STUDIES ON ADSORPTION OF WATER MOLECULES ON A SINGLE-LAYERED CLAY FILM

Abstract

The adsorption of water molecules on the surface of a clay mineral was studied by means of quartz crystal microbalance (QCM) measurements. For the purpose, an ultra-thin film of exfoliated montmorillonite sheets was prepared by the modified Langmuir method. On introducing a nitrogen gas at various humidity, the adsorption and desorption processes of water molecules on a clay film were monitored in terms of mass change. The adsorbed amount of water molecules was compared among the following four films: (F1) a single-layered clay-amphiphile hybrid film, (F2) a single layered clay film, (F3) a double layered clay-amphiphile hybrid film and (F4) a double-layered clay film. The nature of adsorbed water molecules was investigated by comparing the IR spectra between F1 and a cast film.