| Zn O, an important metal-oxide semiconductor material with wide bandgap(~3.7 e V) and large exciton bonding energy(60 me V), can be used in numerous potential applications in gas sensors, solar cell, piezoelectric nanogenerator, and so forth because of its excellent chemical and thermal ability and low cost. However, metal-oxide semiconductor gas sensors usually have some drawbacks such as low sensitivity, bad selectivity and stability, and so on. So,more and more researchers regard that it is important to improve these drawbacks as a object of gas sensors. In fact, a lot of previous studies have suggested that the morphology,composition, shape and size of materials have a strong influence on their properties. Several kinds of strategies are utilized to construct and design some other novel structures in this paper. The morphology and structure of the as-prepared products were also characterized by SEM and XRD technology. So many properties of the product have been studied in our experiment such as gas sensing performance, photoluminescence, and antibacterial properties.Furthermore, a possible mechanism about growth of Zn O was proposed in the paper.Meanwhile, the application of nano zinc oxide as aircraft cargo compartment fire alarming is explored, and the nonlinear relation between sensitivity and the gas concentration is also discussed.1. Flower-like structure ZnO has been synthesized via a one-step wet chemical process using zinc acetate as the raw material at 200 ? reacting for 3 h, 6 h.12 h to explore the mechanism and effect of reaction time on morphology. Rod-like structure of Zn O is of large specific surface area. The results showed great sensing properties: the response value towards 10 ppm ethanol is 14.45.2. Lotus pollen templated porous Zn O microspheres have been prepared via chemical treatment and calcination method. The gas sensing properties of the porous Zn O microsphere based sensor was also measured. The results show that lotus pollen shaped Zn O microspheres have a porous and hexagonal wurtzite structure with a diameter of 10 ?m. The porous Zn O microsphere based sensors has the maximum response of 24.80 and 22.10 to 500 ppm acetone and ethanol respectively at 310o.3. With zinc nitrate and tartaric acid as the raw materials, the Zn O structures doping with different content of yttrium(Y) were successfully synthesized using modified solution combustion method. In the paper, the atomic percentages of yttrium were 0, 1, 2, 4, 8 and10at% by changing the amount of YCl3.6H2 O. Gas sensor fabricated using the 2at% Y-doped Zn O nanostructures exhibits a stronger response and better selectivity toward 100 ppm ethanol as high as 15.97.4. It is known to all that the fire alarming system is one of the most important equipment of aircraft to ensure the safety of the flight. However, the false alarming phenomenon often occurs, which makes a serious threat to the safety of civil aviation transportation. Nano Zn O materials being the sensor probe, an comprehensive intelligent fire alarming system is developed to detector the smoke and harmful gases at the same time. the warehouse fire alarm system has practical application value for the accurate and reliable response of the equipment and the nonlinear relation between sensitivity and the gas concentration is also discussed. |
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