铁氧体基复合纳米材料的制备及在超级电容器中的应用

发布时间：2018-02-10 16:37

本文关键词： 铁氧体聚邻苯二胺氧化锰超级电容器　出处：《江苏大学》2017年硕士论文　论文类型：学位论文

【摘要】：超级电容器,又称为电化学电容器(EC),是一种新型的电能存储装置,其能量密度比电池低得多,而保质期和使用寿命却要比电池长得多。超级电容器的开发和研究主要是为了取代脉冲电池,这主要是因为电池的功率、保质期和循环寿命相对而言较短,而不能满足如今要求越来越高的应用程序。随着技术的发展,研究者们正在大力地研究超级电容器,尤其是其电极材料,这主要是因为电极材料是决定超级电容器综合性能的重要因素。目前超级电容器电极材料主要有以下几种:碳材料、金属氧化物、导电聚合物以及三种材料的复合材料。在以上背景下,本论文以高性能超级电容器的设计和研究为目标,主要开展了以下几个工作:(1)本文通过水热法成功制备出了Mn~(2+)掺杂的Fe_3O_4纳米微球,其中以FeCl_3.6H_2O为唯一铁源,二氯化锰为掺杂剂,乙酸钠为沉淀剂,而乙二醇为还原剂和溶剂。采用透射电子显微镜(TEM)、扫描电子显微镜(SEM)和XRD对其结构进行了表征。并且通过控制反应时间,研究了Fe_3O_4纳米微球的成核和生长机制;以KOH为电解液,研究了所制备的Mn掺杂的Fe_3O_4纳米微球的电化学性能。结果表明:Mn的掺杂量对Fe_3O_4纳米微球的电化学性质有一定的影响。其中,当Mn~(2+)掺杂量为1.5 mmol时,Fe_3O_4-Mn-1.5的电化学性能最佳:在电流密度为1 A·g~(-1)时,比电容高达292.5 F·g~(-1),当电流密度为3.5 A·g~(-1)时,比电容仍能达到121 F·g~(-1),出色的循环稳定性(循环600圈后,电容仍还有83%)。(2)聚苯胺及其衍生物是非常重要的导电聚合物,它们在电化学,聚合物树脂等领域有广泛的应用。为此,本论文以六水三氯化铁为唯一铁源和氧化剂、氨水为沉淀剂和掺杂剂,通过一锅法制备了Fe_3O_4@聚邻苯二胺(POPD-Fe)纳米复合材料。利用扫描电镜、透射电镜、红外光谱、X射线粉末衍射、N2吸附脱附、热重分析等手段对产物结构和组成进行了表征。以KOH为电解液,研究了Fe_3O_4@POPD复合材料的电化学性能。结果显示,POPD-Fe-8(当FeCl_3.6H_2O用量为8mmol的产品)因其合适的微球尺寸,使得样品的电化学性能明显增强,其中包括:较高的比电容(在电流密度为1 A·g~(-1)时,比电容为1252.5 F·g~(-1)),优异的倍率性能(在电流密度为4 A·g~(-1)时,比电容仍能达到619.6 F·g~(-1)),出色的循环稳定性(循环2500次后,电容仍还有79.6%)。(3)此外,本论文在上一个实验的基础上通过加入MnC_(l2),从而制备出带有双金属氧化物导电聚合物复合材料。并且通过改变FeCl_3.6H_2O的用量,研究了其对产品形貌和尺寸的影响。同时,以KOH为电解液,研究了所制备的Fe_3O_4-Mn3O4@POPD(POPD-Fe-Mn)复合材料的电化学性能。结果表明,POPD-MnFe-4(FeCl_3.6H_2O的用量为4 mmol)具有最佳的电化学性能:较高的比电容(在电流密度为1 A·g~(-1)时,比电容1455.9 F·g~(-1)),优异的倍率性能(在电流密度为3 A·g~(-1)时,比电容仍能达到846.9 F·g~(-1)),出色的循环稳定性(循环2500次后,电容仍还有78.3%左右)。
[Abstract]:Supercapacitor, also known as electrochemical capacitor (EC), is a new energy storage device, its energy density is much lower than the battery, and the shelf life and life is much longer than the battery. The research and development of super capacitor is the main pulse to replace the battery, which is mainly because the battery power, shelf life and life cycle is relatively short, and now can not meet the application requirements more and more high. With the development of technology, researchers are vigorously on super capacitors, especially the electrode material, this is mainly because the electrode material is an important factor to determine the comprehensive performance of the super capacitor at present. The super capacitor electrode material mainly has the following kinds: carbon materials, metal oxide, conductive polymer and composite materials of three kinds of materials. Under the above background, this paper research and design of high performance super capacitor The target, mainly carried out the following work: (1) this paper successfully prepared by hydrothermal method Mn~ (2+) Fe_3O_4 nanoparticles doped with FeCl_3.6H_2O, which is the only source of iron, two manganese chloride as the doping agent and sodium acetate as precipitator, and ethylene glycol as the reducing agent and solvent by transmission. Electron microscopy (TEM), scanning electron microscopy (SEM) and XRD were used to characterize its structure. By controlling the reaction time, the nucleation and growth mechanism of Fe_3O_4 nanoparticles; using KOH as electrolyte, electrochemical properties of Fe_3O_4 nanoparticles prepared by Mn doping. The results show that: the effect on the electrochemical properties of Mn doped amount of Fe_3O_4 nanoparticles. Among them, when Mn~ (2+) doped with 1.5 mmol Fe_3O_4-Mn-1.5, the best electrochemical performance at a current density of 1 A - g~ (-1), high specific capacitance of 292.5 F - g~ (-1), when the current Density of 3.5 A - g~ (-1), can still reach 121 F - g~ (-1), the specific capacitance of excellent cycle stability (after 600 cycles, the capacitance is still 83%). (2) conductive polymer polyaniline and its derivatives is very important, they are in electrochemistry and other fields have a wide range of polymer resin application. Therefore, this thesis takes six as the sole source of iron and ferric chloride water oxidizing agent, ammonia as precipitant and doping agent, were prepared by one pot Fe_3O_4@ p o two amine (POPD-Fe) nano composite material. By using scanning electron microscopy, transmission electron microscopy, infrared spectroscopy, X ray diffraction, N2 adsorption desorption. Thermogravimetric analysis on product structure and composition were characterized. With KOH as the electrolyte on the electrochemical performance of Fe_3O_4@POPD composite materials. The results showed that POPD-Fe-8 (when the content of FeCl_3.6H_2O was 8mmol) because of its suitable particle size, the electrochemical properties of the samples Enhanced, including: high specific capacitance (at current density of 1 A - g~ (-1), the specific capacitance was 1252.5 F - g~ (-1)), excellent rate performance (at a current density of 4 A - g~ (-1), can still reach 619.6 F - g~ (capacitance -1)), excellent cycle stability (after 2500 cycles, the capacitance is still 79.6%). (3) in addition, in this paper on the basis of an experiment by adding MnC_ (L2), which was prepared with double metal oxide conductive polymer composite materials. And by changing the amount of FeCl_3.6H_2O research the influence on the morphology and size of the products. At the same time, with KOH as electrolyte were investigated by Fe_3O_4-Mn3O4@POPD (POPD-Fe-Mn) the electrochemical properties of composite materials. The results showed that POPD-MnFe-4 (the amount of FeCl_3.6H_2O was 4 mmol) has the best electrochemical performance: high specific capacitance (at a current density of 1 A - g~ (-1), the specific capacitance of 1455. 9 F. G~ (-1), and excellent rate performance (at current density of 3 A. G~ (-1), the specific capacitance can still reach 846.9 F? G~ (-1), and the excellent cycle stability (2500 times after cycling is still about 78.3%).

【学位授予单位】：江苏大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TM53;TB33

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