Regulation Of Growth Behavior Of ZnO And In₂O₃ Crystal Under Saturation Control

Chemical vapor deposition method is widely used in the preparation of nano-structures due to its simple operation,strong applicability and high quality of growth materials.But in the gas phase method,the growth behavior of nanomaterials is influenced by various experimental parameters?such as temperature,precursor types,etc?,and the experimental repeatability was poor,which makes it difficult to design synthesis of functional nanostructures.In this paper,through in-depth discussion in the gas phase method of the factors on crystal growth can be attributed to the influence of the saturation of reactants,and then the nucleation,crystal surface adsorption migration and growth rate of the nanometer materials were controlled by the saturation of the reactants.The main jobs of this paper are as follows:1.Firstly,In₂O₃ crystals with different morphologies such as octahedron and cubic were prepared by controlling the saturation of metal components and oxygen components during the growth of oxides,the mechanism of the morphology of In₂O₃ nanocrystals was revealed by analyzing the influence of the saturation of the reactants on the crystal growth behavior.Secondly,In₂O₃ crystals with different uniformity of sizes were prepared by controlling the synchronous nucleation of crystals during the experiment,by further controlling the temperature difference between the heating zone and the sinking zone,In₂O₃crystals with different sizes were prepared,and then the influence of the saturation of the reactants on the size of the crystal was analyzed.2.By using Zn+ZnO+C mixed powders as the growth precursors,adjusting the ratio of Zn to ZnO,the bamboo-like structure and chain structure of ZnO were successfully prepared,and by using the negative feedback mechanism in Gibbs-Thomson's law,the mechanism of saturation controlling the diameter changes periodically of the one-dimensional nanostructure was revealed.In addition,the hierarchical nanostructures of ZnO with diamond structure attached to the nanoribbon were prepared by controlling the content of O₂ in the carrier gas?N₂+O₂?,and the two-step growth mode for the secondary growth of metal-rich oxides was proposed.On this basis,nanoscale tetragonal structures of ZnO and hierarchical nanostructures such as nanospheres were prepared by finely controlling the O₂ content in the carrier gas and the temperature difference between the heating zone and the bottom zone.3.ZnO nanostructures with different morphology,size and stoichiometry were prepared by adjusting the saturation of the reactants during the reaction,and their luminescence properties were analyzed.The study showed that:with the change of morphology of ZnO nanostructures from nanorods to nanospheres,the intensity of the visible luminescent region gradually increases,and there is a clear blue shift;with the increase of the size of ZnO nanorods,the visible light emission peak will gradually decrease;for ZnO nanospheres rich in Zn,the luminescence curve coincides with the Zn emission curve when the Zn content is high,and the luminescence curve can be considered as the luminescence curve of Zn and ZnO nanospheres when the Zn and O content ratio is 61.70:38.30.