ZnO nanoparticles were prepared and self-assembled hybrid nanolayers were generated on the surface of silicon wafers using the layer silicate hectorite and PSS (sodium polystyrene-sulfonate) polyelectrolyte. The thickness, light absorption and interference properties of the hybrid films were studied. The influence of layer silicates and polymers on the self-organizing properties of ZnO nanoparticles was examined. Utilization of the nanofilms as optical sensors was investigated: they can adsorb ethanol vapor and their reflection and light interference properties are thereby significantly altered. (c) 2007 Elsevier B.V. All rights reserved.