Sensing Properties of Indium, Tin and Zinc Oxides for Hexanal Detection

The properties of ZnO, In2O3, and SnO2 have been investigated as possible sensing layer in resistive sensors for monitoring hexanal in food applications. Sensors performances were tested at different temperatures (100–350 °C) and analyte concentrations (50–100 ppm). Results showed the ability of the analyzed metal oxides sensors, each one characterized by its own features and operating conditions, to detect hexanal. Moreover, the different oxides response has been also related to their Gibbs free energy of formation. According to preliminary results both indium and zinc oxides show promising sensing characteristics compared to tin oxide.