Gas-sensitive Properties Of ZnO/SnO 2 Based On Nano-support Structure For Ethanol

In this paper,first we prepared three types of one-dimensional ZnO nanostructures by adjusting hydrothermal parameters,such as spindle-shaped ZnO nanorods,cylindrical ZnO nanorods,and ZnO nanowires.In order to improve the gas-sensitivity of single-phase ZnO materials,two kinds of prepared ZnO nanorods/wires were used as backbones to explore the support structure that was most suitable for subsequent composite SnO₂.The morphology characteristics of different one-dimensional ZnO nanomaterials were studied by adding different concentrations of tin ions.Using a fine-pitch interdigitated electrode as a substrate material,different morphologies of ZnO/SnO₂ materials were dispersed in a sol of SnO₂,spin-coated on a substrate,and then prepared into different gas sensors by high-temperature annealing.The gas sensitivity test system places the samples in different concentrations of ethanol gas for gas sensitivity testing.The test results which uses gas sensitive element show that compared with the pure three-dimensional one-dimensional ZnO nanomaterials,the gas-sensitivity of ZnO/SnO₂with the cylindrical ZnO nanorods as the supporting structure is the best,and the selectivity of the materials with SnO₂ to ethanol gas is very good.Great improvement.The best working temperature of ZnO/SnO₂ is 300°C.At 300°C and 350°C,ZnO/SnO₂is more sensitive to the same concentration of ethanol gas than pure one-dimensional ZnO material.When the concentration of complex tin ions is 1 mM,the sensitivity of ZnO/SnO₂ is the highest,and the sensitivity to ethanol gas decreases after the concentration increases.Therefore,the optimum concentration of complex tin ions in this paper is 1 mM.Through analysis and comparison of the test results,it is concluded that cylindrical Zn O nanorods after composite SnO₂ exhibit better gas sensitivity than pure one-dimensional ZnO nanorods and nanowires.