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结合机械力化学与声化学反应,固相合成尖晶石型Zn Al_2O_4纳米颗粒。借助于X射线衍射仪(XRD)、扫描电子显微镜(SEM)和透射电子显微镜(TEM),分析样品的表面形貌、晶体结构、化学成分及反应过程。研究结果表明:振动研磨2 h后,Al颗粒尺寸大约为0.5μm,颗粒内部存在大量的位错缺陷,有利于机械力化学反应。将研磨后的Al颗粒超声水解3 h制备出Al(OH)_3白色乳胶液,经干燥、焙烧后得到多孔、片状、活性γ-Al_2O_3纳米颗粒,颗粒尺寸分布在30~150 nm之间。将Zn O/γ-Al_2O_3固相合成制备出尖晶石型Zn Al_2O_4纳米颗粒,在温度为200~600℃范围内,Zn O/γ-Al_2O_3完成了晶核成型、晶体生长和颗粒成型过程,600℃时颗粒尺寸为30~50 nm,且具有良好的分散性。随着温度升高,颗粒尺寸增大,结晶度提高。
Combined with mechanochemical and sonochemical reactions, the spinel Zn Al 2 O 4 nanoparticles were synthesized by solid state reaction. The surface morphology, crystal structure, chemical composition and reaction process of the samples were analyzed by means of X-ray diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM) The results show that after grinding for 2 h, the Al particle size is about 0.5 μm, and a large number of dislocation defects exist inside the particles, which is in favor of mechanical chemical reaction. The Al (OH) 3 white latex was prepared by ultrasonic hydrolysis of the ground Al particles for 3 h. After drying and calcination, porous, flaky and active γ-Al 2 O 3 nanoparticles were obtained. The particle size distribution ranged from 30 to 150 nm. The Zn O / γ-Al 2 O 3 solid-state synthesis of spinel Zn Al 2 O 4 nanoparticles, the temperature range of 200 ~ 600 ℃, Zn O / γ-Al 2 O 3 completed nucleation, crystal growth and particle forming process, The particle size is 30 ~ 50 nm at 600 ℃, and has good dispersibility. As the temperature increases, the particle size increases and the crystallinity increases.