【作者】 刘程成；

【导师】 宋吉明；

【作者基本信息】 安徽大学 ， 分析化学， 2013， 硕士

【摘要】 钴、钒化合物纳米材料具有独特的结构与性能,被广泛的应用在电化学、磁记录材料、光学、催化、电池、传感等领域,从而成为化学、材料、物理等科学研究与探索的重要方向之一。本文在国内外大量文献调研的基础上,采用一步水热合成方法成功制备出不同形貌与组成的钴、钒化合物纳米材料,并探讨了它们的结构与性能。主要研究内容包括：1.选用亚硒酸钠以及五水合硝酸钴作为前驱物,水合肼作为还原剂,在水热条件下,通过调节反应物配比、反应时间、反应温度控制合成了多种形貌的Co(0.85)Se纳米晶体。通过水热法一步合成了银耳状的非整数比硒化钴,这种结构Co(0.85)Se纳米晶体的比表面积为55.1m2/g。磁性测试结果表明,在室温下这种银耳状的Co(0.85)Se具有顺磁性。将Co(0.85)Se用于催化分解N2H4H2O,实验证明,在最佳的反应条件合成的Co(0.85)Se对N2H4H2O的分解具有优良的催化活性和重复使用性。这对拓宽硒化钴的应用范围具有重要的意义。2.在前期研究工作的基础上,将银耳状Co(0.85)Se纳米晶体与硼氢化钠结合,应用于吸附亚甲基蓝的体系中。在硼氢化钠的作用下,Co(0.85)Se对亚甲基蓝的吸附性能得到了很大的提高。但是,当吸附脱附平衡达到一定时间后,亚甲基蓝会自发从Co(0.85)Se表面解析出来溶解到溶液中。这为染料的回收以及吸附剂的重复利用提供了良好的基础。通过测定吸附过程中溶液的pH以及吸附剂Co(0.85)Se表面的zeta电位,我们推测了可能的吸附机理。同时通过调节硼氢化钠的用量,探讨了硼氢化钠在改变Co(0.85)Se吸附亚甲基蓝性能中所起的作用,并进一步验证推测的吸附机理。3.结合离子液体与五氧化二钒的结构特点,运用水热反应方法,制备了宽度在200-300纳米,长度为几十微米的有机无机复合物V2O5/bmimBr纳米带。通过XRD、X射线光电子能谱(XPS)、元素分析(EA)、电感耦合离子体发射光谱(ICP)等测试手段,探讨了V2O5/bmimBr纳米复合物的组成与结构,以及离子液体与五氧化二钒的作用机制。通过调节离子液体的使用量,研究了离子液体在形成V2O5/bmimBr纳米带过程中的功能。实验证明,离子液插入到V205片层之间后使得产物的导电性得到了很大的提高。更多还原

【Abstract】 Cobalt and vanadium compound nanomaterials show unique structure and special properties, which can be widely used in electrochemistry, magnetic recording materials, optics, catalysts, cell, sense and other fields, and become an important topic in the fields of chemistry, material sciences and physics. In this dissertation, cobalt, vanadium compound nanomaterials with different crystalline structures, composition and morphologies have been synthesized by hydrothermal synthesis process and their properties have been investigated.The main research contents of this dissertation are as follows:Firstly, we chose Co(NO3)26H2O, Na2SeO3as precursors, and N2H4H2O as a reducing agent. Co(0.85)Se with various shapes was synthesized under in the different hydrothermal conditions, including ratio between reactants, reaction temperature and reaction time. The tremelliform Co(0.85)Se nanosheets were obtained via one-step hydrothermal synthesis method in the typical synthesis condition. The tremelliform Coo.85Se nonosheets have a high specific surface area. And magnetism test results show that the tremelliform Co(0.85)Se possesses paramagnetic property at room temperature. Experiments have shown that the Co(0.85)Se nanosheets synthesized under the optimal reaction condition have excellent catalytic activity and reusability in the process of decomposition of N2H4· H2O. The Co(0.85)Se nonosheets were applied to catalyze decomposition of N2H4· H2O as catalyst. This was especially significant in widening the application ranges of cobalt selenide nanomaterials.Secondly, on the basis of previous studies, the tremelliform Co(0.85)Se nonosheets is applied to the adsorption-desorption equilibrium of methylene blue trihydrate in the presence of sodium borohydride. The results display that the Co(0.85)Se nonosheets have efficient catalysis for the decomposition of sodium borohydride. The adsorption capability of the Co(0.85)Se nonosheets for methylene blue trihydrate has been improved obviously due to the decomposition of sodium borohydride. And, after arriving at absorption and desorption balance time, the absorbed methylene blue trihydrate could be released from the surface of Co(0.85)Se nonosheets while sodium borohydride decreased. Thus, the dye and adsorbent can be easily reused and recycled. Zeta potential and the pH of the nanosheets in the equilibrium process has been tested to infer the adsorption mechanism. We explained the function of sodium borohydride by adjusting its amountThirdly, based on the structural characteristics of both vanadium pentoxide and ionic liquid structure, organic-inorganic hybrid V2O5/bmimBr nanobelts with thicknesses of30-50nm and width of200-300nm have been synthesized via a hydrothermal reaction. The composition and structure of the V2O5/bmimBr nanocomposites have been characterized by elemental analysis and inductively coupled plasma (ICP), X-ray photo-electron spectroscopy (XPS), X-ray powder diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR). And the function of ionic liquid in the formation of V2Os/bmimBr has been investigated via adjusting the dosage of ionic liquid in the hydrothermal reaction system. Experiments have shown that the conductivity of the products has got very great improvement after inserting the ionic liquid into the vanadium pentoxide.更多还原