过渡金属化合物复合电极材料的可控制备及其超电容储能性能研究

发布时间：2018-02-27 19:53

本文关键词： 超级电容器分级纳米结构电池型材料电极材料复合材料　出处：《浙江理工大学》2017年硕士论文　论文类型：学位论文

【摘要】：日常生活中,人们对电动汽车和便携式电子设备的兴趣不断飙升,为了满足实际需求,开发新能源存储设备,是我们必须研究的重要课题。超级电容器,又称为电化学电容器,因其具有与锂离子电池和燃料电池互补的优点,例如,高的功率密度、快速的充放电性能、较长的使用寿命、较高的安全性和环境友好兼容性等,已经成为人们设想最有发展前途之一的新能源存储设备。然而,许多电池电极材料其本身具有较低的导电率和储能容量以及较差的倍率性能和稳定性等缺点,因而大大限制了其在超级电容器方面的广泛应用。因此,在本文中,我们介绍几种简单的合成路线用于制备新型电极材料,利用该新型材料理想的微观结构和化学组分来提高材料在使用过程的利用率、离子扩散以及电子传递能力,进而改善材料的不足之处。论文的主要内容如下:(1)通过两步制备法在泡沫镍上生长三维网状的多孔Ni-Mo-O纳米薄片阵列。结果显示,合成的Ni-Mo-O纳米片阵列在电流密度为1 A/g时具有很高的质量比容量,最高可达138.7 m Ah/g,这比纯的NiO纳米片(在1 A/g下为22.3m Ah/g)高很多。另外,Ni-Mo-O纳米片具有很好的倍率性能和显著的循环稳定性,经过5000次循环后其容量还能保持起始值的77.7%。(2)通过两步制备法在泡沫镍上生长三维网状分级的NiCo_2O_4@NiMoO_4核壳纳米线/纳米片阵列。结果显示,合成的NiCo_2O_4@NiMo O_4复合电极在电流密度为10 m A/cm2时具有很高的面积比容量,最高可达805.6μAh/cm2,且具有优异的倍率性能,当电流密度从10 m A/cm2增加到80 m A/cm2时,比容量仍为起始值的83.6%。另外,该电极具有显著的循环稳定性,经过5000次循环,比容量仍有循环前的81.3%。与此同时,使用NiCo_2O_4@NiMoO_4电极材料组装的非对称超级电容器器件,最高电容值为1.54 F/cm2,能量密度最高可达5.64 m Wh/cm3。(3)通过多步制备法在泡沫镍上生长三维网状分级的NiCo_2S_4@Ni(OH)_2核壳纳米线/纳米片阵列。结果显示,合成的NiCo_2S4@Ni(OH)_2复合电极在电流密度为5 m A/cm2时具有很高的质量比容量和面积比容量,最高值分别为240.3 m Ah/g和680μAh/cm2。具有优异的倍率性能,当电流密度从5 m A/cm2增加到100 m A/cm2时,比容量仍为起始值的94.9%。并且,该电极具有显著的循环稳定性,在40 m A/cm2下循环2000次,比容量仍有循环前的81.4%。另外,使用NiCo_2S_4@Ni(OH)_2电极材料组装的非对称液态混合超级电容器器件,最高的能量密度功率密度分别为53.3 Wh/kg和6420 W/kg,同时具有优异的循环稳定性,经过2000次循环,比电容仍为循环前的98.8%。
[Abstract]:In daily life, people's interest in electric vehicles and portable electronic devices is soaring, in order to meet the actual needs, the development of new energy storage devices, is an important subject we must study. Supercapacitors, also known as electrochemical capacitors, Because of its complementary advantages with lithium-ion batteries and fuel cells, such as high power density, fast charge-discharge performance, long service life, high safety and environment-friendly compatibility, etc. It has become one of the most promising new energy storage devices. However, many battery electrode materials have the disadvantages of low conductivity and energy storage capacity, poor rate performance and stability, etc. Therefore, in this paper, we introduce several simple synthetic routes for the preparation of new electrode materials. The ideal microstructure and chemical composition of the new material are used to improve the utilization ratio, ion diffusion and electron transfer ability of the material. The main contents of this paper are as follows: 1) Three-dimensional porous Ni-Mo-O nanocrystalline arrays were grown on nickel foam by two-step preparation method. The synthesized Ni-Mo-O nanochip arrays have high mass specific capacity at current density of 1 A / g. Up to 138.7 m / g, which is much higher than pure NiO nanocrystals (22.3 Ah/ g at 1 A / g). In addition, Ni-Mo-O nanocrystals have good rate performance and remarkable cyclic stability. After 5, 000 cycles, the volume of NiCo_2O_4@NiMoO_4 nanowires / nanowires was maintained at 77.7 / 2 of the initial value.) Three-dimensional reticulated NiCo_2O_4@NiMoO_4 core-shell nanowires / nanowires were grown on nickel foam by a two-step preparation method. The synthesized NiCo_2O_4@NiMo O _ 4 composite electrode has a high area specific capacity at a current density of 10 Ma / cm ~ 2, up to 805.6 渭 Ah路路cm ~ 2, and excellent rate performance. When the current density is increased from 10 Ma / cm ~ 2 to 80 Ma / cm ~ 2, the specific capacity is still 83.6% of the initial value. The electrode has remarkable cyclic stability. After 5000 cycles, the specific capacity of the electrode is still 81.3. At the same time, the asymmetric supercapacitor device is assembled using NiCo_2O_4@NiMoO_4 electrode materials. The maximum capacitance is 1.54 F / cm ~ (2) and the maximum energy density is 5.64 m / cm ~ (3) 路cm ~ (3)) Three-dimensional reticulated NiCo_2S_4@Ni(OH)_2 core-shell nanowires / nanowires are grown on nickel foam by multi-step preparation method. The results show that the maximum energy density is 5.64 m / cm ~ (-3). The synthesized NiCo_2S4@Ni(OH)_2 composite electrode has high mass specific capacity and high area specific capacity at a current density of 5 Ma / cm ~ 2, the highest values are 240.3 m Ah/g and 680 渭 Ahp 路cm ~ 2, respectively. The composite electrode has excellent rate performance. When the current density is increased from 5 Ma / cm ~ 2 to 100 Ma / cm ~ 2, The specific capacity is still 94. 9% of the initial value. Moreover, the electrode has remarkable cycle stability, at 40 Ma / cm 2, the specific capacity is still 81.4. In addition, the NiCo_2S_4@Ni(OH)_2 electrode material is used to assemble asymmetric liquid hybrid supercapacitor devices. The highest energy density power density is 53.3 Wh/kg and 6420 W / kg, respectively, and has excellent cycle stability. After 2 000 cycles, the specific capacitance is still 98.8%.
【学位授予单位】：浙江理工大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TB33;TM53

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