| Zinc Oxide (ZnO) one dimensional nanomaterial, as a direct band gap semiconductor material, on the one hand, has a large band gap (3.37 eV), high exciton binding energy (60 meV), high electron mobility, high break down voltage, large electron saturation velocity, stable chemical property and strong anti-radiation. On the other hand, with the structure of one dimensional, it also has some special advantages, such as large specific surface area and the limitation on electron and light transmission. These characteristics make one dimensional ZnO nanomaterial has a wide range of applications in the fields of electronics, optoelectronics, superhydrophobic materials and gas sensitive materials. In this thesis, focusing on the ZnO nanowire array, we carried out the following researches in the directions of hydrothermal synthesis of ZnO nanowire array, ultraviolet detection and superhydrophobic materials:(1) ZnO nanowire arrays were fabricated on Silicon wafer, ITO glass and Gallium Nitride substrate via hydrothermal method and the growth process of ZnO nanowires was regulated by changing the synthesis conditions such as reaction time, precursor concentration and reactive additives (PEI and ammonia). Through SEM, TEM and XRD, ZnO nanowire arrays were analysised and characterized. On the basis of controllable synthesis of ZnO nanowires, the localization synthesis of ZnO nanowire arrays on Silicon and PDMS was achieved by lithography and ZnO-Copper Oxide and ZnO-Tungsten Oxide nanomaterials with hierarchical structure were also synthesized through atomic layer deposition (ALD). These experimental results lay a foundation for the following studies.(2) ZnO single nanowire ultraviolet photoconductive detector was fabricated by using the focused ion beam. By comparing the different ZnO nanowire detectors with different diameters, ZnO nanowires with smaller diameter show better photoelectric response. A vertical ZnO nanowires photoconductive detector was fabricated by using the ZnO nanowire arrays growth on the ITO glass. Compared with the single nanowire detector, this vertical device has the advantages of simple process and easy to large-scale preparation. With the use of porous carbon template, single crystal ZnO nanowire arrays with porous structure were fabricated on the ITO glass. Compared with ZnO nanowire arrays, porous ZnO nanowire arrays have larger specific surface area and stronger optical absorption properties, which make porous ZnO show a stronger photoelectric response characteristic.(3) Two-tire rough ZnO nanowire arrays were fabricated through twice hydrothermal process. After hydrophobic modification, the ZnO thin films showed good superhydrophobic properties with high contact angle, low sliding angle and stable superhydrophobic property. Furthermore, a three-tier rough superhydrophobic film was fabricated, with the use of bottom-up hydrothermal growth process and top-down lithography and etching process.Compared with other superhydrophobic surfaces with lower surface roughness, the three-tier rough surface has the best superhydrophobic property, with the largest contact angle, the smallest sliding angle and the strongest impact resistance. It proves that superhydrophobic properties can be improved by increasing the roughness of the superhydrophobic film.(4) Based on the research of photoelectric detection and superhydrophobic characteristics of ZnO, a porous ZnO film with UV detection and superhydrophobic property was fabricated. ZnO thin films were deposited on a porous Carbon film through ALD. After calcinations, ZnO films with porous network structure were prepared. This method provides a simple and easy large-scale production method for preparing nanoscale porous ZnO film. After surface hydrophobic treatment, the porous ZnO film has the properties of UV detection and superhydrophobic. This UV photodetector with self-cleaning function is expected to be applied in a wide range of conditions. |
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