Binary and Ternary Oxide Nanostructured Multisystems for Gas Sensors

Abstract

Currently, semiconductor gas sensors are among the most common types of sensing devices for detecting dangerous and toxic gases in the atmosphere. However, their characteristics should be improved in order to use them in practical applications. In this study, techniques have been developed to improve the response of sensors based on zinc oxide nanowires. The first technique is to modify the chemical composition of the nanowires by forming a shell of ternary Zn-Sn-O and Zn-Fe-O systems on their surfaces. Another approach is to control the surface concentration of oxygen vacancies by adding sodium bromide during the synthesis of zinc oxide nanowires. The surface chemical composition and the sensor properties of the samples were studied. It was found that the sensor responses of samples of ternary oxide systems and zinc oxide samples with a high content of oxygen vacancies exceeded the sensor responses of the samplewithinitial zinc oxide nanowires. The results are analyzed in terms of the interaction involving reducing gases with metal oxides.

Keywords

• zinc oxide
• gas sensor
• ternary oxide
• hydrothermal synthesis
• oxygen vacancies
• adsorption sites