【作者】 崔三观；

【导师】 邱建丁；

【作者基本信息】 南昌大学 ， 分析化学， 2011， 硕士

【摘要】 由于碳纳米管复合材料不仅能保留各成分的优良性能,而且在光学、化学及其它性能方面表现出单独材料所没有的性能而引起科技工作者广泛关注。这些材料的合成过程对其在电化学中的催化性能有着重要影响。因此,选择适当的合成途径,改善传统纳米材料制备过程中的不足是十分重要的。本文采用简便高效的方法制备了几种具有代表性的碳纳米管复合材料,如NiO/MWNTs、CeO2/MWNTs、Pt/MWNTs和Pd/MWNTs,其优良的电催化活性表明这些材料在生物传感器和燃料电池中有很广阔的应用前景。开展了以下的研究工作：1.采用简单高效的水热合成法制备NiO/MWNTs纳米复合材料,并将其用于蛋白质的固定化和生物传感器件的设计。选用肌红蛋白作为直接电化学研究的模型,该材料固定肌红蛋白后能促进其活性中心与电极表面之间的直接电子传导,并且所构建的传感器对H2O2具有很高的电催化活性。由于所构建的生物传感器具有操作简单、响应迅速、良好稳定性和重现性等特点,使该材料在蛋白质的固定化及制备第三代生物传感器方面有很广泛的应用前景。2.本文采用CeO2/MWNTs纳米复合材料固定肌红蛋白并构建了新型电化学生物传感器。紫外-可见吸收光谱及电化学研究表明该材料不仅可以很好地保留肌红蛋白的生物活性,还可加速其与电极表面之间的直接电子传输。低米氏常数(63.3μM)表明该传感器对H2O2有很高的亲和力和电催化活性。该纳米材料在蛋白质的固定化和第三代生物传感器构建等领域具有重要的应用前景。3.采用新颖方法把单分散的Pt纳米粒子负载于MWNTs表面,即在三甘醇中高温裂解Pt(acac)2,原位合成单分散的Pt/MWNTs纳米复合材料。采用X射线衍射法、扫描电镜和透射电镜等对复合材料结构进行表征,发现可通过改变Pt(acac)2/MWNTs质量比有效调控Pt纳米颗粒粒径及其在MWNTs表面负载密度。电化学研究表明该材料对甲醇、氧气等有很高的电催化活性,在燃料电池和生物传感器领域展现出广阔的应用前景。4.通过在三甘醇中高温裂解Pd(acac)2,在MWNTs表面原位生成单分散Pd纳米粒子。采用X射线衍射法、扫描电镜和能量色谱等对Pd/MWNTs纳米复合材料结构进行表征,结果表明本方法能高效地制备该复合材料。电化学检测表明该材料对甲醇、甲酸和过氧化氢等有很高的电催化活性,可望进一步应用于燃料电池和生物传感器领域。更多还原

【Abstract】 Canbon nantubes nanocomposites have drawn much attention by scientific researchers because they not only show their unexpected combined properties of the original components, but also cause changes in optical, chemical, or other performances compared with those of the individual components. The synthetic method of these materials has great influences on their electrocatalytic application. Thus, improving the traditional preparation process of nanomaterials is very important. In this thesis, simple and effective methods were developed to synthesize several kinds of representative canbon nantubes nanocomposites including NiO/MWNTs, CeO2/MWNTs, Pt/MWNTs and Pd/MWNTs. The excellent electrocatalytic activity of these materials indicates potential applications in biosensors and fuel cells. The following researches have been carried out.1. A novel matrix, multiwalled carbon nanotubes supported nickel oxide nanoparticles composite nanomaterial (NiO/MWNTs), for immobilization of protein and biosensing was designed using a simple and effective hydrothermal method. Using myoglobin (Mb) as a model, the direct electrochemistry of immobilized Mb indicated the matrix could accelerate the electron transfer between protein’s active sites and the electrode. The modified electrode shows excellent electrocatalytic activity toward the reduction of H2O2 without the help of an electron mediator. The simple operation, fast response, acceptable stability, and reproducibility of the proposed biosensor indicated its promising application in protein immobilization and preparation of the third generation biosensors.2. A novel myoglobin-based electrochemical biosensor was developed. It is based on a nanocomposite prepared from multiwalled carbon nanotubes that were coated with ceria nanoparticles. UV-vis and electrochemical measurements displayed that the nanocomposite provides a biocompatible matrix for the immobilization of myoglobin (Mb) and also facilitates direct electron transfer between its active center and the surface of the electrode. Immobilized Mb exhibits excellent electrocatalytic activity toward the reduction of hydrogen peroxide (HP). The low apparent Michaelis-Menten constant of 63.3μM indicates high bioactivity and enhanced affinity to HP. This study also shows that the nanocomposite is a promising support for immobilization of proteins and for the preparation of third-generation biosensors.3. A novel approach to the synthesis of mono-dispersed platinum nanoparticles (Pt NPs) on multiwalled carbon nanotubes (MWNTs) has been proposed. With this method, we successfully assembled mono-dispersed Pt NPs on MWNTs. The method involved the in situ high-temperature decomposition of the precursor, platinum (Ⅱ) acetylacetonate (Pt(acac)2), in liquid polyols. We used X-ray diffraction, scanning electron microscopy, and transmission electron microscopy to characterize the resulting MWNTs covered with Pt NPs (Pt/MWNTs). We found that the size of the Pt NPs and the coverage density on MWNTs could be tuned easily by changing the reaction temperature and the initial mass ratio of Pt(acac)2 to MWNTs. Electrocatalytic measurements showed that the Pt/MWNTs had excellent catalytic activities in the electrooxidation of methanol and in the oxygen reduction reaction. These Pt/MWNTs have potential applications in fuel cells and biosensors.4. Nearly monodisperse palladium nanoparticles (Pd NPs) have been successfully decoration of multiwalled carbon nanotubes (MWNTs) by in situ high-temperature decomposition of the precursor Pd(acac)2 and MWNTs in liquid polyols. X-ray diffraction, scanning electron microscopy, and energy dispersive spectrometer were used to characterize the final products, indicating the feasibility of our methods for synthesis of Pd/MWNTs nanocomposite. Electrocatalytic characterization demonstrated that these Pd/MWNTs have excellent catalytic activities in the electrooxidation of methanol, formic acid and hydrogen peroxide. The in situ synthesised Pd/MWNTs system displayed good electrochemical activity, with promising applications in fuel cells and biosensors.更多还原