Institute of Fundamental Technological Research

Two-component Langmuir–Blodgett film has been fabricated from equimolar mixture of 5-[[1,3-dioxo-3-[4-(1-oxooctadecyl)phenyl]propyl]amino]-1,3-benzenedicarboxylic acid with cetylamine. Porous one-component derivative of this film has been obtained by removing of cetylamine. Both films have been investigated as sensing layers of the surface acoustic wave sensors for vapors of methanol and ethanol in air. These films react on the alcohol vapors. Time of the sensor reaction is less than 2 s and this reaction is reversible. The response parameters of the sensor depend on the kind of the alcohol and the structure of the layer. An explanation of the observed differences in the behavior of both layers in contact with vapors of the alcohols has been proposed.

Self-assembled monolayer, Langmuir–Blodgett films, Organic films, Surface acoustic wave, Sensors, Alcohols, Methanol, Ethanol

In this work a structure of a ultrasonic chemical sensor with organic monomolecular layer as well as introductory measurement with the help of a set-up constructed in IFTR PAS are presented. Chemical composition of this layer is an equimolar mixture of 5-[[1,3-dioxo-3- [4-(1-oxooctadecyl) phenyl] propyl] amino] – 1,3 – benzenedicarboxylic acid (DA) and cetylamine (CA). The thickness of this layer is equal to dimension of one molecule. The sensor layer was deposited on one channel of the bi-channel sensor delay line (made from lithium niobiate) by means of the Langmuir–Blodgett method. The chemical sensitivity of this sensor to some mixtures of air with vapor of volatile organic compounds has been investigated

ultrasonic chemical sensor, Langmuir–Blodgett layers, air-organic vapor mixtures, volatile organic compounds