SUPRAMOLECULAR AND POLYMERIC STRUCTURES FOR GAS SENSORS

Molecular, supramolecular and polymeric compounds are particularly suitable for tailoring chemically sensitive coatings of thin-film gas sensors to monitor volatile organic compounds (VOCs). The molecular recognition occurs either by specific key/lock interactions in the first monolayer, or by incorporation in the bulk. The separation of surface reactions from bulk dissolution effects is deduced from the thickness dependence of sensor effects of 'prototype materials', which show different mechanisms of molecular recognition. Experimental and theoretical concepts for fine-tuning sensor properties by an empirical optimization or theoretical understanding of sensing mechanism are stressed. This requires extra information about the thin-film structures obtained from additional microscopic and spectroscopic investigations.