Al基金属玻璃去合金化制备超级电容器

发布时间：2018-05-05 07:47

  本文选题：超级电容器 + 金属玻璃　； 参考：《安徽工业大学》2017年硕士论文

【摘要】：与日常生活所使用的电池相比,电化学电容器(也被称作超级电容器)因为其具有高的能量密度、快速充放电的能力、使用寿命长、循环稳定性好已经成为下一代具有潜力发展的储能设备。赝电容超级电容器的电极材料主要是过渡族金属氧化物组成,如RuO2、NiO、CoO、MnO2等。然而过渡族金属氧化物的价带与导带的价隙比较窄,从而导致它们的导电性比较差。这是超级电容器存在的一个主要问题。本论文针对超级电容器这个问题,以提高材料的导电性为出发点,进行了电极材料的设计、合成、性能的研究。对电解液的浓度、去合金化的时间、去合金化前驱体的成分和状态进行调控,完成了非晶合金作为超级电容器电极材料的系统研究。本论文介绍的以非晶合金作为前驱体的新型结构材料有望在超级电容器上得到应用。本论文主要研究内容如下:(1)非晶前驱体的去合金化工艺对电容性能的影响。通过对Al82Ni6Y6Co3Cu3金属玻璃去合金化来制备多孔电极材料,并将此电极材料应用于超级电容器的研究。研究了去合金化时间和去合金化溶液(KOH溶液)的浓度两个因素对制备出的电极的形貌结构和电化学性能的影响。实验结果表明:制备出的电极材料是孔洞尺寸大约为50 nm的三维连续多孔结构;去合金化时间对电极的电容性能有很大影响,随去合金化时间的增大,比电容先增大后减小,在4 M KOH溶液里,50 min是最佳的去合金化时间;合金化溶液的浓度对电极的电容性能有很大影响,随着浓度的增大度越大前驱体腐蚀的就更快,导致形成的纳米多孔材料的孔壁更细,使材料的比表面积更大和活性点更多,导致比电容更大,且4 M KOH腐蚀50 min可以达到最大比电容1.22 F cm-2。(2)非晶前驱体成分对电容性能的影响。通过对Al85-xNi6Y6Co3CuX(x=1,3,5)三种成分的金属玻璃进行去合金化的处理制备超级电容器电极材料,主要研究铜的掺杂含量对电极材料的电化学性能的影响。实验结果表明:在相同的去合金化工艺下(室温下,4 M KOH去合金化50 min),Al82Ni6Y6Co3Cu3在Al85-XNi6Y6Co3CuX(x=1,3,5)三种成分里电容性能最好,即合适的铜含量掺杂可以得到更好的电容性能;铜含量的掺杂可以改变电极材料的串联等效电阻,使Al82Ni6Y6Co3Cu3在Al85-XNi6Y6Co3CuX(x=1,3,5)三种成分里的串联等效电阻最小,从而使其具有最大的比电容值。(3)非晶前驱体的退火温度对电容性能的影响。通过对Al82Ni6Y6Co3Cu3金属玻璃在不同的退火温度下保温相同的时间进行去合金化的处理制备超级电容器电极材料,主要研究退火温度对电极材料的电化学性能的影响。实验结果表明:退火温度越高制备的电极材料的多孔尺寸就越大;在421℃退火下制备的电极材料的比电容性能最好,面积比电容可以高达2.05 F cm-2。
[Abstract]:Electrochemical capacitors (also known as supercapacitors) because of their high energy density, ability to charge and discharge quickly, and long service life compared with batteries used in daily life. Good cycle stability has become the next generation of potential energy storage equipment. The electrode materials of pseudo-capacitor supercapacitors are mainly composed of transition group metal oxides such as Ruo _ 2O _ (2) NiO _ (2) CoO _ (2) MNO _ (2) and so on. However, the valence gap between the valence band and the conduction band of the transition metal oxides is relatively narrow, which leads to their poor conductivity. This is a major problem with supercapacitors. In order to improve the conductivity of supercapacitors, the design, synthesis and performance of electrode materials are studied in this paper. The concentration of electrolyte, the time of dealloying, the composition and state of the precursor of dealloying were regulated, and the system study of amorphous alloy as electrode material of supercapacitor was completed. In this paper, the new structure materials with amorphous alloy as precursor are expected to be used in supercapacitors. The main contents of this thesis are as follows: 1) the effect of the dealloying process of amorphous precursor on the capacitance performance. Porous electrode material was prepared by dealloying Al82Ni6Y6Co3Cu3 metallic glass and applied to supercapacitor. The effects of the time of dealloying and the concentration of dealloying solution (Koh) on the morphology and electrochemical properties of the prepared electrode were studied. The experimental results show that the electrode material prepared is a three-dimensional continuous porous structure with the pore size of about 50 nm, and the dealloying time has a great influence on the capacitance performance of the electrode, and with the increase of the dealloying time, the capacitance increases first and then decreases. In 4 M KOH solution, 50 min is the best time for dealloying, the concentration of alloying solution has a great influence on the capacitance performance of the electrode, and the precursor corrodes more quickly with the increase of the concentration. The resulting nano-porous materials have thinner pore walls, larger specific surface areas and more active points, resulting in larger specific capacitors. The maximum specific capacitance is 1.22F cm-2.2) the effect of the composition of amorphous precursor on the capacitance performance can be achieved by 50 min corrosion of 4m KOH. The electrode material of supercapacitor was prepared by dealloying three kinds of metallic glass (Al85-xNi6Y6Co3CuXX). The effect of doping content of copper on the electrochemical properties of electrode material was studied. The experimental results show that under the same dealloying process (4M KOH dealloying at room temperature for 50mins, Al82Ni6Y6Co3Cu3 in Al85-XNi6Y6Co3Cu3Cu3) has the best internal capacitance properties, that is, the better capacitive properties can be obtained with proper doping of copper. The doping of copper can change the series equivalent resistance of the electrode material and make the series equivalent resistance of Al82Ni6Y6Co3Cu3 in the three components of Al85-XNi6Y6Co3CuXTX _ 3) minimum, thus making it have the maximum specific capacitance value. 3) the effect of annealing temperature of the amorphous precursor on the capacitance performance. Supercapacitor electrode materials were prepared by dealloying Al82Ni6Y6Co3Cu3 metallic glasses at different annealing temperatures for the same time. The effect of annealing temperature on electrochemical properties of electrode materials was studied. The experimental results show that the porous size of the electrode materials prepared at higher annealing temperature is larger, and the specific capacitance of the electrode materials annealed at 421 鈩，

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