Preparatin And Optical Properties Of Hierarchical Structure Arrays Of1-D Zinc Oxide Nanorods

Nanomaterials, due to their unique physical and chemical properties, have become one of the research hotspots in the fields of functional materials and electronic devices in recent years. The continuous progress of nano preparation techniques and the unique features of hierarchical nanostructures allow for better improvements in material properties and thus this field has attracted much interest. Based on the synthesis theory of one-dimensional zinc oxide nanorods, hierarchical structures of zinc oxide composed of nanorod and nanoneedle/nanorod and nanowires/segmented structure were synthesized, and then the formation mechanism of nanostructure was studied by considering the hydrothermal methods, the influencing factors of synthesis conditions and the relationship between structure and performance. The constructed hierarchical nanostructures have potential application prospects in terms of fields such as UV laser transmitter and cathode field emission devices.One-dimensional (1-D) ZnO nanorod array films were synthesized by a low-temperature solution method on the modified FTO glass substrate with ZnO seed layers. The growth direction was perpendicular to the FTO substrate, along the C-axis orientation. The samples had high quality and very low defect density.Similar to the hydrothermally synthesis of zinc oxide array, hierarchical structure arrays films consisted of both zinc oxide nanorods and zinc oxide nanoneedles were successfully constructed by one-step low-temperature solution method, using the triblock copolymer F127as the structure directing agents. The structure and morphologies of array films were systematically analyzed by X-ray diffraction, field emission scanning electron microscopy, and high resolution transmission electron microscopy. A "time-sharing growth" mechanism was put forward for the explanation of hierarchical structure formation.Hierarchical structure array films of one-nanorod/multi-nanowires were synthesized in the same way as nanorod/nanoneedles structure. The influence of concentration diversity and sample size on sample morphology was discussed. The fluorescence properties and field emission performance of zinc oxide hierarchical nanostructures were deeply investigated. Results show that such zinc oxide nanoarray has both excellent UV emission property and field emission performance.Hierarchical structure array films with segmented morphology were synthesized through a twice-low-temperature solution procedure by adjusting process parameters such as growth time, concentration of growth media, growth frequency, etc. The photoluminescence result shows that there is a strong bluelight and greenlight emission peek in the spectrum, which is mainly caused by the structure defects in the hierarchical array film. In summary, the synthesis of zinc oxide films with such structure provides useful experiential reference for similar research in the future and may greatly enrich the diversity of nanostructure materials, thus contributing to a wider application of such kind of materials.