LANGMUIR-BLODGETT MULTILAYERS BASED ON COPPER PHTHALOCYANINE AS GAS SENSOR MATERIALS - ACTIVE LAYER GAS INTERACTION-MODEL AND CONDUCTIVITY MODULATION

Blodgett films of copper(II) rakis((3,3-dimethylbutoxy)carbonyl)]phtha locyanine and pper(II)[tetrakis(n-butoxycarbonyl)]phthalocyanine have been studied as sensitive elements of gas sensors. Moreover, alternate LB films of the two compounds and LB films obtained from a 1:1 mixtur e of them have also been investigated. In particular, after exposure t o NO2 oxidizing gas, the electrical conductivity of the materials goes through a maximum at a temperature of about 170 degrees C correspondi ng to the maximum sensitivity to the gas. The sensitivity and stabilit y of the response of the active layers to NO2 are discussed as well as the application of these materials as the sensitive elements for gas- sensing devices.