| Nanomaterials,the most basic and active area of nanotechnology,is a cross between the materials science and nanotechnology,which affect the development and economy of society deeply.Due to their special properties,such as small effect,surface size effect,quantum size effect,and etc,which differ from bulk substances and single molecular,nanomaterials have huge potential applications in electronics,solar cell, ceramics,biology,medicine and many other fields.With the understanding of these unique properties and application deeper,more and more attention is paid to fabricating nanomaterials and nanostructures.Although since 1980s,synthesis of zero-dimensional materials has made great development,the synthesis of one-dimensional(1D) and two-dimensional(2D) materials is still challengable.Because of their special electronic, optical,magnetic and mechanical properties,their application in microelectronics and nano-electronics will be the crucial problem to solve and new research area to study.ZnO,a direct and wide band gap semiconductor ofⅡ-Ⅵgroup,has an energy gap of 3.37eV at room temperature.Nanostructured ZnO materials are the excellent unity of nanomaterials and semiconductors which can be widely applied for LCD displays,solar cells,protecting coatings,gas sensors,solid illuminations and UV optical devices. Although fabrication of ZnO nanomaterials has reached new high level,there still exsit many problems which are hard to solve.Therefore,synthesis of controllable ZnO nanomaterials and investigation of their optical properties attract more attention.This paper focuses more on fabricating ZnO nanomaterials and characterizing their optical properties.On one hand,two techniques,CVD and electrospinning,were adopted to synthesize ZnO nanowire and nanofibers.On the other hand,the optical properties of ZnO nanomaterials were mainly tested by PL and FTIR;their microstructure and phase composition were studied by XRD,TEM/HRTEM,SEM, EPM,and EDS.This paper includes three contents as follow:1.ZnO nanofibers were synthesized by combing electronspinning and sol-gel method, using PVA and Zn(Ac)2·2H2O as raw materials.And then the microsture and optical properties of nanofibers were investigated in the experiment.The results indicated that all the final samples were ZnO nanomaterials with hexagonal wurtzite structure;the PL spectra at room temperature show that there exsits three emission bands,a strong violet emission band at 416nm(2.98eV),a blue band at 149nm(2.70eV) and a weak green band at 530nm(2.34eV).2.Fabricating ZnO nanofibers with typical n-type dopants Al by electronspinnin method using PVA and Zn(Ac)2·2H2O as precursors.The four ZnO nanofibers with different Al3+ concentration were then characterized and their optical properties were also investigated.The results showed that the obtained samples were all hexagonal wurtzite-type ZnO and the introduction of Al dopants affected the morphology and microsture of ZnO nanofibers great.Meanwhile,strong violet emission,blue emission and weak green emission could be found in all samples in their PL spetra at room temperature.3.ZnO nanowire arrays were obtained on silicon wafers by chemical vapor deposition method of heating the mixture of ZnO and graphit powders in molar ratio of 1:1.5 in different experimental parameters.The effect of experimental parameters on the morphology and structure of ZnO nanowires were studied,so were their optical properties.The results revealed that both increasing the heating rate and decreasing the heat preservation time could resulte in less diameter and high quality nanowires. Moreover,the distance between silicon wafer and mixed powders was not an important aspect in controlling the morphogogy and microsture of nanowirs.And the PL spetra showed that there existed two emission bands:one was the ultraviolet emission band which corresponded to near band edge,and anther was the wide green emission band which was caused by the electronic excitoning of the vacancy level in the ZnO semiconductor.
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