Hydrothermal Synthesis and Gas Sensing Properties of Zinc Hydroxostannate

Introduction. Currently in gas sensing there is an urgent need to improve performance, including sensor response and speed, as well as to reduce operating temperatures. To achieve these goals, multicomponent oxide systems are being studied. Various modifications of Zn–Sn–O system are among the most promising materials. Aim. To develop techniques for the hydrothermal preparation of zinc hydroxostannate nanoparticles using different precursors. Active layers for gas sensors were created and tested using these synthesized nanoparticles. Materials and methods . Zinc hydroxostannate nanoparticles were synthesized using hydrothermal methods for 6 hours at a temperature of 90 °C. Two techniques using different precursors were used to obtain the samples. The samples were then analyzed using scanning electron microscopy, X-ray diffraction, and X-ray photoelectron spectroscopy. Based on the optical spectroscopy results, the band gap of zinc hydroxostannate was determined. Gas sensing properties of the nanoparticles were investigated under different conditions, including target gases, temperatures, and exposure to UV radiation. Results. A comprehensive study of the synthesized structures has shown that the nature of their interaction with target gases is different depending on the synthesis technique. Specifically, ZnSn(OH)6_1 samples demonstrate a response at room temperature and are highly rapid. This is attributed to the predominance of zinc ions on their surface. In contrast, ZnSn(OH)6_2 samples, with a surface rich in tin ions surrounded by OH groups, require additional activation by UV radiation to achieve a response at room temperature. At the same time, the response and recovery times are in the order of hundreds of seconds. Conclusion. The paper explores the potential of using zinc hydroxostannate nanoparticles created through the hydrothermal process for room temperature gas sensors. The key factor in this study is the selection of the synthesis technique.