含锗化合物纳米材料的制备及其性能

发布时间：2018-08-05 10:01

【摘要】：近年来,由于含锗化合物纳米材料在半导体、光电、光催化、锂离子电池等领域有着广泛的应用,因此有关其制备及性能的研究已经成为固体化学中相当热门的研究领域。基于上述原因,本文采用低温溶剂热法制备出了一系列具有高纯度和较高结晶度的含锗化合物纳米材料及其与还原氧化石墨烯的纳米复合物,并利用XRD、HRTEM、SEM、 EDX、XPS、FT-IR、Raman等手段对产品进行了系统的表征。同时,对温度、包覆剂、pH和包覆剂浓度、水热时间、反应物浓度等因素对产品组成、形貌、晶相的影响进行了讨论。在此基础上,还对光催化制氢活性、电化学行为以及光电化学行为进行了初步探讨。经过较为系统的研究,我们获得了一些有意义的成果：首先,我们分别以GeCl4、硫代乙酰胺作为锗源和硫源,采用乙酸作为溶剂,通过溶剂热技术在低温下(140。C)成功地制备出了具有高纯度和较高结晶度的GeS2纳米片。对其光催化制氢(采用0.1 mol/L Na2S和0.1 mol/L K2SO3作为牺牲剂)性能的测试测试结果表明：对于光还原水制氢反应来说,所制得的GeS2纳米片是一个性能较为优良的光催化剂。在它的催化作用下,在13 h光照的期间内,体系的平均析氢速率为144μmol·g-1·h-1。这些实验结果预示着高纯度、高结晶度的GeS2纳米片在光催化领域具有-定的应用价值。此外,我们所建立的制备方法有可能为今后单层GeS2纳米片的制备提供研究思路。其次,采用溶剂热法一锅制备出了GeS2-rGO纳米复合物。对其电化学、光电化学行为的研究表明：rGO含量的引入使得GeS2的光电转换性能大幅度增强。当rGO的含量为4.8%时,GeS2-rGO纳米复合物电极的光电流密度是GeS2电极的12倍。此外,该纳米复合物还是一个潜在的锂离子电池的电极材料。其首次放电容量高达2469.3 mAh.g-1。由此,可以推测所得到的GeS2-rGO纳米复合物有可能在光电检测装置和锂离子电池中得到应用。最后,我们以Ge02为锗源,二水合乙酸锌为锌源通过水热技术制备出了Zn2GeO4纳米棒。发现当使用油胺时得到的是长径比较大的纳米棒,而使用乳酸则只能得到纳米短棒。pH对于Zn2GeO4的形成至关重要。只能在弱碱性环境中,才能得到高质量的产物。对其光学和电化学性质的研究预示所制得的Zn2GeO4纳米材料是一种潜在的光催化剂。
[Abstract]:In recent years, nanomaterials with germanium compounds have been widely used in the fields of semiconductors, optoelectronics, photocatalysis, lithium ion batteries and other fields. Therefore, the study of their preparation and properties has become a very hot research field in solid chemistry. Based on the above reasons, a series of high purity is prepared by using low temperature solvothermal method. The nanomaterials of germanium containing compounds with high crystallinity and their nanocomposites with the reduction of graphene oxide are systematically characterized by means of XRD, HRTEM, SEM, EDX, XPS, FT-IR, Raman and so on. At the same time, the composition, morphology and crystal phase of temperature, coating agent, pH and coating agent, hydrothermal time, and reactant concentration are made. On this basis, the activity of photocatalytic hydrogen production, electrochemical behavior and photochemical behavior were also discussed. After a systematic study, we obtained some meaningful results: first, we use GeCl4, thioacetamide as a germanium source and sulfur source, acetic acid as a solvent, through dissolution. GeS2 nanoscale with high purity and high crystallinity was successfully prepared at low temperature (140.C) at low temperature. The test results of its photocatalytic hydrogen production (using 0.1 mol/L Na2S and 0.1 mol/L K2SO3 as a sacrificial agent) showed that the prepared GeS2 nanoscale was a better performance for the reaction of hydrogen production by the light reduction water. Excellent photocatalyst. Under its catalysis, the average hydrogen evolution rate of the system in the period of 13 h light is 144 mol. G-1. H-1. these experimental results indicate high purity and high crystallinity GeS2 nanoscale has a definite application value in the field of photocatalysis. Furthermore, the preparation method we have established is likely to be a single layer GeS2 nanoscale in the future. The preparation of rice slices provides a research idea. Secondly, the GeS2-rGO nanocomposites are prepared by a solvent heat method. The electrochemical behavior of the GeS2 has been studied. It is shown that the introduction of rGO content makes the photoelectric conversion performance of GeS2 greatly enhanced. When the content of rGO is 4.8%, the photocurrent density of the GeS2-rGO nanocomposite electrode is GeS2 12 times that of the electrode. In addition, the nanocomposite is a potential electrode material for lithium ion batteries. The first discharge capacity is up to 2469.3 mAh.g-1.. It is possible to speculate that the obtained GeS2-rGO nanocomposites are likely to be applied in the photoelectric detection device and lithium ion batteries. Finally, we use Ge02 as the germanium source and two hydrate acetic acid. Zn2GeO4 nanorods were prepared by hydrothermal technology as zinc source. It was found that when oleamine was used, a nanorod with a larger diameter was obtained, and the use of lactic acid only obtained nanoscale.PH for the formation of Zn2GeO4. Only in a weak alkaline environment, a high quality product could be obtained. The predicted Zn2GeO4 nanomaterials are a potential photocatalyst.
【学位授予单位】：上海应用技术学院
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TB383.1

【相似文献】