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Using ZnO metal semiconductor materials in the gas sensor is always the researchhot spot, due to the sensor made from zinc oxide has many advantages such as low cost,good selectivity, fast responding speed and high sensitivity, and it can be widelyemployed in detection of toxic and inflammable gases and metering of atmosphericgases.In this thesis, Zn(NO3)2and C6H12N4were used as the raw materials, using thehydrothermal method by controlling the growth substrate, reacting temperature， pH ofthe reacting solution and adding different amount of glycol to synthesize ZnO. Therod-like, bamboo-like, flower-like and reticular-like ZnO had been successfullyfabricated at different conditions, among them the reticular-like and flower-like ZnOthat synthesized on the two sides of the aluminum plates have been fabricated at the firsttime, and it’s also proved the repeatability. And the products were analyzed by scanningelectron microscope, X-Ray Diffraction, photoluminescence and so on, the growthmechanism of the different morphologies that synthesized at different conditions werealso discussed.It has improved in the thesis that the morphology of TiO2substrate has little effecton the morphology of ZnO, but the morphology of ZnO grows much more uniformlywith the substrate. The pH also plays an important role in the morphology of ZnO, totaldifferent morphologies would be fabricated under different pH. When the pH=14, amorphology with large specific surface area can be fabricated. The changing reactingtemperature doesn’t change the morphologies of the ZnO thin film which wasassembled by ZnO microrods that synthesized on the substrate, but only change themorphologies that grew on the ZnO thin film. The addition of glycol made the flake-likestructures with high surface to volume ratio much easier to be got. And when theaddition of glycol is10ml, the flake reaches the nanometer level. Depend on all factorsthat can influence the ZnO morphology in this thesis, the conditions were modified touse aluminum as the growing substrate, added10ml glycol and made the pH of reactingsolution to14by adding NaOH particles into the solution, after the hydrothermalreaction, a reticular-like and flower-like ZnO structure has fabricated successfully.
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