Detection mechanisms on chemiresistors with a sensitive layer based on nanostructured oxides


The project aims at preparation of nanostructured oxidic materials (SnO2, WO3, ZnO a In2O3), intended for sensitive layers of chemiresistors, and study of surface reactions taking place during the detection of selected classes of gaseous analytes (oxidizing gases - O2, NO2; reducing gases - H2, CH4; gases/vapours that can form hydrogen bonds with oxidic surface - H2O, NH3; unsaturated hydrocarbons; alcohols and ketones) on these layers. In the framework of the project a new diagnostic tool (NAP XPS) will be utilized for measurement of photoelectronic spectra during exposition of sensitive layer by gaseous analyte. It will enable to reveal the mechanisms of surface reactions during detection. There will be explored both experimental and theoretical consequences between nanoscale (morphology of sensitive layer, chemism of detection processes on its surface, corresponding modulation of electrophysical parameters of the layer) and macroscale - properties of chemiresitor as an integral device (sensitivity, selectivity, stability).