丝瓜络碳基电极材料的超级电容器性能研究

发布时间：2018-01-22 01:22

本文关键词： 超级电容器生物质丝瓜络多孔碳材料氧化锰　出处：《青岛大学》2017年硕士论文　论文类型：学位论文

【摘要】：超级电容器(也可以成为电化学电容器)是一种介于电池和传统电容器的重要的新型能源装置。传统的碳材料在一定程度上加剧了气候变暖和环境恶化。所以,采用废弃的生物质作为碳基材料的原料引起了广泛的关注。本文寻找到了一种成本低、产量高的生物质丝瓜络为原料,探讨不同活化剂对丝瓜络多孔炭形貌、结构和其电化学性能的影响。为了进一步增加多孔炭的比电容,发挥金属氧化物在充放电过程中的赝电容行为,在多孔炭上负载锰氧化物,研究复合材料的电化学行为。本文选择丝瓜络生物质为碳前驱体,经H2O2和NaOH处理并碳化,结果表明丝瓜络碳材料具有分级多孔管状结构。以预处理的丝瓜络为碳原料,分别采用KOH和ZnCl2为活化剂制备丝瓜络多孔碳材料。XRD图谱表明LSPC-KOH和LSPC-Zn Cl2均为无定型炭。LSPC-KOH BET比表面积分别高达3400 m~2/g,具有更多的中孔。在两电极6 M KOH超级电容体系中0.5 A/g电流密度下LSPC-KOH和LSPC-ZnCl2的比电容值分别为178 F/g和98 F/g。无论是扩散电阻还是传质电阻,LSPC-KOH均小于LSPC-ZnCl2。通过对比,PC-KOH无论是在孔结构还是比表面积,甚至是电化学性能都得到了较好的效果。将优选的高比表面积丝瓜络多孔碳材料,通过浸渍后再经过不同温度下热处理方法制备了一系列氧化锰负载的多孔炭样品,XRD结果表明500℃热处理所得到的是MnO2,600℃热处理所得到的是MnO,随着温度的增加,锰氧化物的结晶度升高。SEM分析表明负载氧化锰前后多孔炭的结构和形貌基本一致,温度升高,氧化锰从薄膜转换为颗粒状。BET和孔径分布分析结果表明负载氧化锰前后孔径变化幅度不是太大,负载前后比表面积和总孔容降低。电化学性能分析表明:具有优异的充放电可逆性和稳定性,而且等效串联电阻较小。当500℃下热解制备的复合材料电化学性能效果最好,其比电容值从多孔炭的178 F/g提高达到了212 F/g,比电容增加了19.1%。
[Abstract]:Super capacitor (also can become the electrochemical capacitor) is an important new energy device between a battery and conventional capacitors. Conventional carbon materials to a certain extent exacerbated the climate change and environmental degradation. Therefore, the use of waste biomass as raw material of carbon based materials have attracted great attention. In this paper, looking for at a low cost, high yield of biomass Loofah as raw materials of different activators on Luffa porous carbon morphology, structure and its electrochemical performance. In order to further increase the specific capacitance of porous carbon, metal oxide play in the process of charging and discharging pseudocapacitive behavior in porous manganese oxides carbon on the electrochemical behavior of composite materials. This paper chooses the loofah biomass as carbon precursors by H2O2 and NaOH and carbonation, results show that loofah carbon materials with hierarchical porous tubular structure. The pretreatment of Loofah as carbon raw materials, respectively using KOH and ZnCl2 as the activating agent for preparation of Luffa porous carbon materials.XRD LSPC-KOH and LSPC-Zn Cl2 spectra showed that both amorphous carbon.LSPC-KOH BET surface area were as high as 3400 m~2/g, with more holes in two. 6 M KOH super capacitor electrode system in the current density of 0.5 A/g LSPC-KOH and LSPC-ZnCl2 specific capacitance values were 178 F/g and 98 F/g. both the diffusion resistance and mass transfer resistance, LSPC-KOH is less than LSPC-ZnCl2. by comparing the PC-KOH, both in the pore structure or surface area, and even the electrochemical performance has been good results. The preferred high surface area of Luffa complex porous carbon material by Impregnation after porous carbon samples a series of manganese oxide supported by different temperature heat treatment method, XRD results show that the 500 degree heat treatment by MnO2600 is hot Processing obtained is MnO, with the increase of temperature, the crystallization degree of manganese oxide increased.SEM analysis showed that the manganese oxide before and after the structure and morphology of porous carbon consistent temperature, manganese oxide from the film is converted to granular.BET and pore size distribution analysis showed that manganese oxide aperture changes before and after the load is not too large, before and after the loading the specific surface area and total pore volume decreased. The analysis shows that the electrochemical properties: excellent discharge reversibility and stability, and the equivalent series resistance is small. When the best electrochemical performance of composite effect under 500 DEG C prepared by pyrolysis, the specific capacitance of porous carbon from 178 F/g increased to 212 F/g, an increase of 19.1%. specific capacitance

【学位授予单位】：青岛大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TM53;TB383.4

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