节点文献
TiO2纳米结构及n-型TiO2纳米结构/p-型金刚石异质结制备、表征及性质研究
Preparation, Chacteristics, and Properties of TiO2 Nanostructure and Nano n-TiO2/p-diamond Heterojunctions
【作者】 苑举君;
【导师】 李红东;
【作者基本信息】 吉林大学 , 凝聚态物理, 2011, 博士
【摘要】 二氧化钛(TiO2)是一种重要的直接带隙半导体材料,具有优异的物理、化学性质,在光催化降解有机物、场发射、太阳电池及传感器等方面等诸多领域具有重要的研究价值和广阔的应用前景。本论文的主要工作即是在多种衬底上制备TiO2纳米结构,并深入研究其光电特性。主要包括在化学气相沉积(CVD)硼掺杂金刚石(BDD)膜上制备TiO2纳米结构,并研究其电学特性及光催化特性;在硅(Si)单晶衬底上制备了开口的锐钛矿相TiO2纳米片;并研究上述纳米结构的光催化性能。获得了一些创新结果,具体研究内容如下:1.采用水热法,以ZnO为过渡层,在硼掺杂金刚石膜上生长了高密度的金红石相TiO2纳米棒。ZnO过渡层对生长TiO2纳米棒提供了非常有效地异相成核点。通过增加反应温度及反应时间,提高了TiO2纳米棒结晶质量,改变了其形貌及尺寸。获得了具有良好整流特性n-型TiO2纳米棒/BDD异质结结构,该结构具有较好的场发射特性。2.利用液相合成法,以ZnO纳米棒阵列作为模板,在硼掺杂金刚石膜上制备了TiO2纳米管阵列。获得了具有明显的整流特性的n-型TiO2纳米管/BDD异质结结构,该异质结结构表现出优异的光催化性能及很好重复性。3.利用液相合成法,以ZnO纳米片作为模板,在Si衬底上制备了开口的TiO2纳米片,并具有较好的光催化性能。
【Abstract】 Titania (TiO2) is an important direct band gap semiconductor material. nanomaterials has recently attracted much attention due to its distinguished physical and chemical properties making it suitable for many applications such as photocatalysts, electron field emitter, photovoltaic cells, and chemical sensors.In this thesis, we prepare rutile TiO2 nanorods (NRs) on boron-doped diamond (BDD) film; synthesize anatase TiO2 nanotube (TiNT) arrays on chemical vapor deposited (CVD) BDD substrates and study their electrical and photocatalytic properties. The hollow and open-ended TiO2 nanosheets is fabricated on Si substrate and study their photocatalytic properties. Some innovative results are obtained and the details of our work are as follows:1. The rutile TiO2 NRs has been hydrothermally synthesized on BDD film with a ZnO buffer layer. It is proved that the ZnO buffer layer provide uniform heterogeneous nucleation sites effectively for the grown TiO2 NRs. Additionally, with the increase of reaction temperature and reaction time, TiO2 NRs exhibit a better crystallinity. The n-type TiO2 NRs/BDD heterojunctions have been prepared and the current-voltage (I-V) examination results represent a good diode behavior. Additionally, the TiO2 NRs/BDD heterojunction possesses better electron field emission performance with a low turn-on electric field and high current density.2. Anatase TiO2 nanotube (TiNT) arrays have been fabricated on a p-type boron-doped diamond substrate by a liquid phase deposition method using a ZnO nanorod template. It is proved that the ZnO nanorod template has important effect on the morphology of the TiNT. The n-typeTiNT/BDD heterojunctions have been prepared and the current-voltage (I-V) examination results represent a good diode behavior. The n-type TiNT/p-type diamond heterojunction structures which are realized show significantly enhanced photocatalytic activities with good recyclable behavior.3. The hollow and open-ended TiO2 nanosheets film is firstly fabricated on Si substrate. The TiO2 nanosheets are realized show good photocatalytic activities.
【Key words】 TiO2 nanorod; TiO2 nanotube; boron-doped diamond; hydrothermal reaction; liquid phase deposition; electron field emission; photocatalytic activities;