氧化钒与导电聚合物电化学复合及超电容应用

发布时间：2018-06-03 00:43

本文选题：氧化钒 + 聚苯胺　；参考：《东北大学》2014年博士论文

【摘要】：超级电容器是高功率密度的新型储能器件,提高能量密度是提高其性能的关键。扩展超级电容器电极材料储能电位窗可有效提高电容器工作电压,进而大幅度提高电容器能量密度。本文利用氧化钒(V2O5)与导电聚合物原位电化学复合,制备了具有高储能电位窗的无机-有机复合超级电容器电极材料,并组装了模拟超级电容器,探讨其储能应用。为了进一步改善电容器性能,还尝试了组装非对称型超级电容器。无机-有机复合既可综合无机组分与有机组分优势,又可诱导无机-有机协同效应,对发展新型储能材料很有意义。本文首先在含有0.1 M苯胺和0.05、0.1、0.2、0.3、0.4及0.5 M VOSO4的溶液中,利用苯胺电化学聚合和V205电化学沉积,进行聚苯胺(PANI)和V2O5的电化学共沉积,制备V2O5-PANI复合膜VP-0.5、VP-1、VP-2、VP-3、VP-4和VP-5。利用X-射线衍射(XRD)研究V2O5的晶型,利用红外光谱(FT-IR)研究V2O5和PANI的振动吸收。利用扫描电子显微镜(SEM)观测V2O5-PANI复合膜的形貌,发现与V2O5电化学共沉积有助于PANI的一维生长,分析了电化学沉积溶液中硫酸氧钒浓度对复合膜形貌的影响。利用循环伏安、恒电流充放电和交流阻抗技术研究了V2O5-PANI的电化学性能,发现得益于无机-有机复合,V2O5-PANI的储能电位窗扩展至1.6 V (-0.9～0.7 V vs. SCE)。V2O5-PANI以纳米棒形式存在时,有利于电极活性物质与电解液接触,进而充分发挥储能性能,在5 M LiCl溶液中,以0.5 mA/cm2的电流密度充放电时,VP-1比电容达443 F/g,远高于类似条件下制备的V2O5 (217 F/g)和PANI (241 F/g)。然后在含有0.1 M LiClO4、0.1M VOSO4的PBS溶液中(pH=6.86)分别加入吡咯使其浓度分别为0.1、0.05、0.03、0.025和0.02 M,在0.7 V电位下进行吡咯的电化学聚合及V205电化学沉积,制备V2O5-聚吡咯(PPy)复合膜VPy-1、 VPy-2、VPy-3、VPy-4和VPy-5。利用XRD研究V2O5-PPy上V2O5的晶型,利用FT-IR研究V2O5和PPy的振动吸收特征峰。利用SEM观测了V2O5-PPy的形貌,发现V205对PPy也有一维生长诱导作用。利用循环伏安、恒电流充放电和交流阻抗技术研究了V2O5-PPy的电化学性能。V2O5-PPy上的PPy可发生阴阳离子双掺杂,因此V2O5-PPy复合膜的储能电位窗高的2.0V(-1.4-0.6 V vs. SCE)。以一维结构存在有利于V2O5-PPy上活性物质与电解液接触,进而充分发挥储能性能,其中VPy-3在5 M LiCl溶液中,以4.5 mA/cm2的电流密度充放电时,比电容达412 F/g,远高于类似条件下制备的V2O5 (181 F/g)和PPy (257 F/g).以LiCl/PVA凝胶为电解质,分别以V2O5-PANI复合膜VP-1和V2O5-PPy复合膜VPy-3组装了对称型超级电容器VP-1//VP-1和VPy-3//VPy-3。利用循环伏安和恒电流充放电实验测试了电容器性能。得益于电极材料的高储能电位窗,VP-1//VP-1可在1.6 V的高电压下工作,因此能量密度大大提高,可达69Wh/kg。并表现出优越的循环稳定性,5000次充放电后,电容维持率达92%。VPy-3//VPy-3工作电压进一步提高,达2.0 V,能量密度则高达82 Wh/kg。 5000次充放电后,电容维持率为80%。VP-1//VP-1和VPy-3//VPy-3均表现出优越的柔韧性,电容器弯曲0°、60°、120°和180°角度后,比电容基本不受影响。在0.05 M RuCl3·H2O、0.1M KCl、0.01 M HCl和0.05M NH4Ac溶液中,电化学沉积Ru02薄膜。以RuO2为正极,分别以VP-1和VPy-3为负极,组装非对称型超级电容器VP-1//RuO2和VPy-3//RuO2。VP-1//RuO2和VPy-3//RuO2工作电压均可高达2.0 V,其能量密度分别为83.3 Wh/kg和91Wh/kg,5000次充放电后,电容保持率分别为90%和86%。
[Abstract]:Supercapacitor is a new type of energy storage device with high power density. Increasing the energy density is the key to improve its performance. The expansion of the electric potential window of the supercapacitor electrode material can effectively improve the working voltage of the capacitor and greatly increase the energy density of the capacitor. In this paper, the V2O5 and the conductive polymer in situ electrochemical combination are made. An inorganic organic composite supercapacitor electrode material with a high energy storage potential window was prepared, and an analog supercapacitor was assembled to discuss its energy storage application. In order to further improve the performance of the capacitor, an unsymmetrical supercapacitor was assembled. The organic synergistic effect is of great significance to the development of new energy storage materials. First, in the solution containing 0.1 M aniline and 0.05,0.1,0.2,0.3,0.4 and 0.5 M VOSO4, electrochemical copolymerization of aniline and V205 electrochemical deposition was used to prepare the electrochemical co deposition of polyaniline (PANI) and V2O5 to prepare VP-0.5, VP-1, VP-2, VP-3, VP-3, VP-3, VP-2, and V2O5. P-5. uses X- ray diffraction (XRD) to study the crystalline form of V2O5 and uses the infrared spectroscopy (FT-IR) to study the vibration absorption of V2O5 and PANI. The morphology of the V2O5-PANI composite film is observed by scanning electron microscope (SEM). It is found that the electrochemical co deposition with V2O5 is helpful to PANI one-dimensional growth, and the compound membrane form of the concentration of vanadium sulfate in the electrochemical deposition solution is analyzed. The electrochemical performance of V2O5-PANI was studied by cyclic voltammetry, constant current charge discharge and AC impedance technique. It was found that the energy storage potential window of V2O5-PANI expanded to 1.6 V (-0.9 ~ 0.7 V vs. SCE).V2O5-PANI in the form of nanorods, which was beneficial to the contact between the electrode active substance and the electrolyte. In the 5 M LiCl solution, the VP-1 specific capacitance is 443 F/g when the current density is 0.5 mA/cm2, which is much higher than that of V2O5 (217 F/g) and PANI (241 F/g) prepared under similar conditions. 0.02 M, the electrochemical polymerization of pyrrole and V205 electrochemical deposition at 0.7 V potential were used to prepare the V2O5- polypyrrole (PPy) composite membrane VPy-1, VPy-2, VPy-3, VPy-4 and VPy-5.. By means of cyclic voltammetry, cyclic voltammetry, constant current charge discharge and AC impedance technique, the PPy on the electrochemical performance of V2O5-PPy can be doped with both yin and yang ions, so the energy storage potential window of the V2O5-PPy composite membrane is high in 2.0V (-1.4-0.6 V vs. SCE). The existence of one dimension structure is beneficial to the active substance and electrolysis on V2O5-PPy. In 5 M LiCl solution, the specific capacitance of VPy-3 is 412 F/g, which is much higher than that of V2O5 (181 F/g) and PPy (257 F/g) under similar conditions. The LiCl/PVA gel is the electrolyte, and the V2O5-PANI composite membrane VP-1 and the composite membrane are assembled to assemble symmetry, respectively. The type supercapacitors VP-1//VP-1 and VPy-3//VPy-3. test the performance of the capacitor by cyclic voltammetry and constant current charge discharge experiments. Thanks to the high energy storage potential window of the electrode material, the VP-1//VP-1 can work at 1.6 V high voltage, so the energy density is greatly improved, and it can reach 69Wh/kg. and show the superior cycle stability and 5000 charge discharge. After the 92%.VPy-3//VPy-3 operating voltage is further increased to 2 V and the energy density is up to 82 Wh/kg. 5000 times, the capacitor maintenance rate is superior to 80%.VP-1//VP-1 and VPy-3//VPy-3. After the capacitor is bent 0, 60, 120 and 180 degrees, the capacitance is basically unaffected. In 0.05 M RuCl3 H2O 0.1M KCl, 0.01 M HCl and 0.05M NH4Ac solution, electrochemical deposition of Ru02 film. RuO2 as the positive pole, VP-1 and VPy-3 as negative poles respectively, the assembly of asymmetric supercapacitor VP-1//RuO2 and VPy-3//RuO2.VP-1//RuO2 and operating voltage can be up to 2, the energy density is 83.3, respectively, after the 5000 charge discharge, electricity. The retention rate is 90% and 86%., respectively.
【学位授予单位】：东北大学
【学位级别】：博士
【学位授予年份】：2014
【分类号】：TM53;O646.54

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