Effect of the composition and structure of metal oxide nanocomposites on the sensor process when detecting reducing gases

Abstract

The effect the nature of metal oxide components, quantitative and qualitative composition, structure of binary metal oxide nanocomposites, and temperature have on the physicochemical processes that occur during the detection of reducing gases and are responsible for the efficiency and selectivity of sensors based on these composites is considered. The relationship between the mechanisms of the conductivity and sensor effect in composites is determined. The crucial role of electron transfer between metal oxide components with different work functions leading to the mutual charging of these components is noted. The mechanisms of electronic and chemical sensitization of the sensor effect in composite materials consisting of metal oxides with various electronic and chemical properties are discussed. The important role of the way composite materials are obtained is noted. The effect of small clusters of one oxide on the surfaces of nanoparticles of other components, formed during the synthesis of composites via impregnation, is studied. Systems consisting of composite nanofibers of the core–shell type based on metal oxides of different natures are considered. It is shown that by changing the nature of the components and their relative location in the nanofibers, the sensitivity and selectivity of a sensor system can be adjusted for different chemical compounds.