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Synthesized by a relatively simple and low-temperature solution method with different particle size, morphology rules uniform monodisperse ZnSnO3 cubic crystal, needle-like structure were synthesized by a complexing agent-assisted hydrothermal method, microspheres, hollow nanoparticles self-assembled the zinc stannate crystals of different morphologies of the cage-like structure, massive self-assembled microspheres, the structure of hexagonal flake, massive self-assembly octahedral template-free solution method step synthesis of a series of stannate (cadmium stannate , tin, magnesium, the stannate copper, and tin, manganese) nanocrystals. And the use of X-ray diffraction (XRD), adsorption specific surface area (BET), X-ray photoelectron spectroscopy (XPS), field emission scanning electron microscope (FESEM), transmission electron microscopy (TEM), UV - visible absorption spectroscopy (UV-Vis) , the electron resonance paramagnetic spectroscopy (EPR), as well as gas sensing testing means to characterize the resulting material structure, morphology and gas sensing performance, the results are as follows: low temperature solution method using an extremely simple step successfully is prepared with morphology rules, uniform particle size, and the mono-dispersed particle size of the zinc stannate cubic crystal. And through control of the reaction temperature, the successful regulation of the prepared zinc stannate cubic crystal grain size (40-600 nm). According to the different nodes of the field emission scanning electron microscope photograph, to infer of zinc stannate cubic crystal formation mechanism of nucleation - self-assembly process. The preparation of zinc stannate cubic crystal sensor formaldehyde gas exhibits a high sensitivity, fast response and a shorter recovery time. With of zinc stannate cubic crystal particle diameter becomes gradually smaller than the surface area increases gradually, the forbidden band width becomes small, the gas detection sensitivity is gradually increased, wherein at 0 OC when preparing a particle diameter of about 40 nm the zinc stannate cubic nanocrystals minimum detection limit of formaldehyde up to 1 ppm or less. Synthesized a series of different morphologies of zinc stannate materials complexing agent assisted synthesis hydrothermal reaction. The complexing agent acid, complexing ability, molecular structure and other characteristics of the morphology. Successfully prepared by changing the type of complexing agent (such as: nano-needle-like structure, nanoparticles self-assembled microspheres, hollow cage-like structure, massive accumulation of self-assembled microspheres with different morphologies the stannate micro / nanomaterials Hexagonal self-assembled structures and massive accumulation of octahedral structure). Different morphologies of zinc stannate micro / nano-materials for ethanol gas showed different sensitivity, in which the needle-like structure has the highest sensitivity, followed by self-assembly of nanoparticles microspheres, hollow cage-like structure, massive self-assembled microspheres , the six-party piece, massive self-assembly octahedron. This is because the needle-like structure smaller particle size has a high specific surface area, on the other hand, because of the one-dimensional structure is conducive to the transfer of electrons, leading to the gas sensor has a higher gas sensing performance. Complexing agent assisted synthesis, is expected to be achieved through the choice of a specific complexing agent to control the synthesis of the different structures of the target product. Using a universal, simple and low-temperature solution method, in the case of no surface-active agents and templating agent auxiliary step process for the preparation may be dispersed in an aqueous solution of cadmium stannate, tin, magnesium, tin, manganese, and tin acid copper colloidal nanocrystals. And their gas sensing performance: the cadmium stannate the optimum operating voltage than the tin, magnesium, tin, manganese, copper tin oxide, better application potential. The cadmium stannate nanocrystals gas sensor for ethanol has a very good response and better gas sensing selectivity, testing equipment that can be applied to make drink driving.
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