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Since microns or nano-sized hollow sphere density, large surface area , the ball wall is generally nanostructures often exhibit many different from the physical and chemical properties of the solid particles , such as optical , electrical, magnetic properties , in many areas , such as light, electricity , magnetic, sustained-release capsules , drug delivery , lightweight filler , selective adsorption and catalytic potential application value , therefore , in recent years, with different compositions of hollow micro / nano spheres have aroused great interest. In this paper, a very simple template-free hydrothermal synthesis method , nano-structured hollow spheres prepared and characterized by X -ray diffraction (XRD), field emission scanning electron microscope (FESEM) and transmission electron microscopy (TEM) and other means of samples characterization , mainly related to the following: 1, through the Ni (CH 3 COO) 2 and ammonia hydrothermal reaction at 140 ℃ 12h, prepared a diameter of about 1 2 μm porous Ni (OH) 2 nano-structured hollow microspheres , heat treated at 600 ℃ were obtained nanostructured porous NiO hollow microspheres . And further discussed the formation mechanism of hollow spheres . 2, through a non- template simple hydrothermal method to prepare the high phase transition temperature of TiO 2 nano-structured hollow microspheres . Using XRD, FESEM and TEM products were characterized , the results show that , TiO 2 hollow microspheres of a diameter of about 1 ~ 2μm, 900 ℃ phase transition has not yet occurred . Rhodamine B through photocatalytic prove TiO 2 hollow microspheres with good catalytic activity. 3, with rare earth nitrate - a mixed solution of glucose as the precursor solution through the water treatment and the subsequent firing process , synthesis of micron RE 2 O 3 : Eu 3 (RE = Y, Gd) hollow spheres , using XRD, FESEM, TEM and fluorescence spectra of products were characterized , the results show that the wall of the sphere diameter of about 30nm nanocrystalline build from , hollow ball with good luminescent properties .
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