【作者】 靳军；

【导师】 马建泰；

【作者基本信息】 兰州大学 ， 物理化学， 2008， 博士

【摘要】 本论文主要探索功能化碳纳米管来作为苯类衍生物的吸附剂和光电转化材料;研制了一种新型锡膜的电化学传感器及其对重金属离子的检测,研究了它的最佳使用条件;探索了二氧化碳荧光传感器的研制及其应用研究。主要内容归纳如下:1.在多壁碳纳米管的纯化过程中使其开口,然后用FeN₃的水溶液利用毛细现象来实现碳纳米管的管内填充,在560℃下分解,然后用氢气在900℃还原,使其产生磁性;利用偶氮二异丁氰在恒温的条件下裂解,产生烷烃链的自由基来修饰碳纳米管,再用NaOH使其水解,使其具有水溶性。通过这两步修饰使碳纳米管既具有磁性,又具有水溶性。由于碳纳米管对苯及其衍生物具有良好的吸附性能,经过双功能化的碳纳米管,用来除去水中苯及其衍生物且重复使用的。2.利用偶氮二异丁氰在恒温的条件下裂解,产生的烷烃链的自由基来修饰碳纳米管,侧壁修饰卟啉在碳纳米管的量可达60%。这种方法极大地提高的卟啉及其配合物化学键合在碳纳米管上的量,这些材料的荧光光谱证明它们可以有效地作为光电或能量转化的材料。3.我们首次制备一种新型的锡膜修饰电极（SnFE）,使用溶出伏安法检测来重金属离子。这种电极是在0.1 M的乙酸钠的缓冲溶液中和一定的电位下原位制备。我们对主要的几个参数如电解电位、沉积时间、pH等进行了优化。沉积时间为120s,在20-140ppb范围内对Pb（Ⅱ）的响应电流和浓度之间具有良好的线性关系。与铋膜电极相比对Pb（Ⅱ）具有很好的选择性。SnEF对Zn（Ⅱ）、Cd（Ⅱ）和Pb（Ⅱ）进行了检测,SnFE具有背景电流低且锡环境友好性等优点,有望在重金属离子的检测取代汞电极。4.采用相转移的方法,将亲水性的荧光染料pyranine修饰在非亲水性二氧化硅的凝胶的矩阵中,研究不同硅源对二氧化碳传感器的影响。研究了用TiO₂掺杂在二氧化硅的矩阵来提高其对二氧化碳检测的灵敏度。更多还原

【Abstract】 The aim of this dissertation is to explore the functionalization of Mutli-Walled carbon nanotubes （MWNTs）. Magnetic Fe nanoparticle functionalized water-soluble MWNTs were prepared, and used for the removal of aromatic compounds in water and re-use; MWNTs porphyrin modified serve as an efficient electron acceptor; we prepared a new Tin film sensor for heavy metals and a CO₂ fluorescent sensor. The main contents can be summarized as follows:1. The head of MWNTs were opened, when they were purified. MWNTs were dispersed in Fe（NO₃）₃·9H₂O solution with the help of an ultrasonic bath. After draining excess water on a rotary evaporator with a vacuum pump and washing with distilled water, the resulting materials were reduced using H₂ at 560℃and at 900℃successively. The inner empty cavity of the nanotubes has magnetic nanoparticles. We used the carbon radicals to modified the MWNTs and made them water-soluble. Finally. We got the magnetic Fe nanoparticle functionalized water-soluble MWNTs for the removal of aromatic compounds in water and re-use.2. Antenna-acceptor composites of porphyrin and its complexes(Co²⁺, Zn²⁺) covalently linked mulitwalled carbon nanotubes（MWNTs） as many light-harvesting antenna of MWNTs was constructed by free radicals generated using decomposition of azodiisobutyronitrile （AIBN）. MWNTs were derivatized up to about 60 wt. % with functionalizing moieties of the porphyrin. UV-Visible spectroscopy and the absorption and fluorescence of these complexes show that the carbon nanotubes serve as an efficient electron acceptor3. A tin film electrode （SnFE） was reported for the first time as a possible alternative for electrochemical stripping analysis of trace heavy metals. The SnFE was prepared in situ on a glassy carbonsubstrate electrode and employed in combination with either anodic stripping voltammetry or stripping chronopotentiometry in nondeaerated solutions of 0.1 M acetic acid. Several key operational parameters influencing the electroanalytical response of SnFE were examined and optimized, such as deposition potential, deposition time, and composition of the measurement solution. The SbFE exhibited well-defined and separated stripping signals for both model metal ions, Zn（II）、Cd（II） and Pb（II）, surrounded with low background contribution. The electrode range from 20 to 140 ppb for both test metal ions for Pb（II） obtained after a 120 s deposition step, and good reproducibility. When comparing the SnFE with the commonly used bismuth film electrode recently introduced , the newly proposed electrode offers a remarkable selective to detect the Pb（II） hence contributing to the wider applicability of electrochemical stripping techniques in connection with "mercury-free" electrodes.4. The sol-gel process was used to prepare organically modified silica glass in which the fluorescent pH-sensitive reagent 1-hydroxypyrene-3,6,8-trisulfonate was entrapped. An ion-pair approach was used to incorporate the hydrophilic dye in the hydrophobic silica glass. Good sensitivity to gas phase carbon dioxide was observed in the 0-30% range, with rapid response and we used the principle of Mie scattering TiO₂ was doped in the silica glass, the sensitivity for the same concentration of CO₂ was markedly improved compared with the non doped TiO₂ silica glass.更多还原