Investigation On The Synthesis And Field Emission Properties Of In₂O₃ And ZnO Nanostructures

In this thesis,In2O3 and ZnO nanostructures have been successfully synthesized by chemical vapor deposition route under atmospheric pressure. Meanwhile, the field emission properties of In2O3 and ZnO nanostructures coated on the free-standing carbon nanotubes film were investigated in detail. This thesis contains the following works and innovations:1. In2O3 nanostructures were successfully synthesized with uniform size and high yield through the chemical vapor deposition route. The relationship between the reaction conditions and the morphologies of the as-prepared products was investigated. Field emission measurement showed that the nanorods with rectangular cross-section had excellent field emission properties because of their sharp tips, which make the structure a promising candidate in FE device applications. In addition, the room-temperature photoluminescence showed obvious UV located at 396nm and visible emissions at 541 and 623nm.2. We successfully synthesized nanostructural ZnO coated on the free-standing carbon nanotubes film by a chemical vapor deposition route for the first time. These ZnO nanostructures combined well with the MWNTs to form ZnO-MWNTs composite structure. The field emission measurements were carried out. It was found that they had better FE properties than pure MWNTs films, showing a low turn-on field and a high field enhancement factor. The glucose sensing have also been studied. The multi-layer structure (PDDA/GOx/ZnO/MWNTs) was prepared as the electrode improving enzyme immobilization for enhancing bioelectrocatalytic activity of glucose sensor.3. The free-standing carbon nanotubes films were fabricated by a simple filtration method comprising three steps. These free-standing carbon nanotubes films acting as the substrate have significant advantages. Firstly, it can be made as large as possible via a simple filtration method. The diameter of the free-standing carbon nanotubes films is only decided by the size of the filtration membranes. So if we obtained larger filtration membranes, we will be able to yield larger carbon nanotubes films. Secondly, since the carbon nanotubes film is free-standing, it will be convenient to be arbitrary tailored and stuck on other substrates, such as Si, GaN, and Al2O3 substrates.