Zeolite films prepared via the Langmuir–Blodgett technique

Micrometer sized zeolite particles were found to form relatively stable particle monolayers at the air–water interface when spread from a chloroform dispersion. For these layers compression isotherms were recorded. The presence of polyelectrolytes in the aqueous subphase was found to have a significant influence on the compression behaviour of the films and on the degree of orientation of the zeolite particles in the film. The transfer of the floating thin film onto a solid substrate via the Langmuir–Blodgett (LB) technique proved to be possible. The parameters influencing the deposition of zeolite particles on different solid substrates are discussed. The resulting films are analysed with respect to the orientation of the individual zeolite particles by means of optical microscopy. The LB films are characterised by a dense packing of zeolite particles with a predominant ‘side-on’ orientation of the zeolite crystals. The adhesion of the zeolites to solid substrates is improved by a plasma pre-treatment of the substrate and by the presence of polyelectrolytes in the subphase.