氮硫共掺杂碳微球的溶剂热法制备及电化学性能研究

发布时间：2017-12-27 21:42

本文关键词：氮硫共掺杂碳微球的溶剂热法制备及电化学性能研究　出处：《燕山大学》2016年硕士论文　论文类型：学位论文

【摘要】：掺杂碳微球具备优异的电化学特性,在超级电容器、燃料电池、锂离子电池等领域拥有巨大的应用潜力,吸引了众多科研工作者的关注。本论文采用溶剂热法制备了氮硫共掺杂碳微球并在高温下利用氢氧化钾对其进行活化处理,采用透射电子显微镜、扫描电子显微镜、氮气吸脱附测试、拉曼分析、X射线光电子能谱分析、循环伏安测试、线性扫描伏安测试、恒流充放电测试、交流阻抗测试等分析表征手段对所得样品的形貌结构、元素成分及电化学特性做了分析测试,研究结果如下:以乙腈为氮源,二硫化四甲基秋兰姆为硫源,在400℃下,经过24 h反应,成功合成了氮硫共掺杂碳微球(NS-CMSs)并在不同温度下对其进行了活化处理,电化学测试结果显示活化温度为800℃时制备的NS-CMSs-800在碱性溶液中具有最高的氧还原催化活性,与商业化的20 wt%铂碳催化剂相比,不仅具备四电子转移过程,同时表现出了更优秀的甲醇耐受性以及长期稳定性。分别以升华硫、硫脲、TMTD为不同硫源,以乙腈为氮源制备氮硫共掺杂碳微球。在400℃下,经过16 h反应,成功合成了氮硫共掺杂碳微球。在750℃下经过KOH活化后,氮硫共掺杂碳微球具有多级孔道结构,比表面积为397.4~413.8 m~2g~(-1),在0.1 Ag~(-1)的电流密度下,具有242~295 Fg~(-1)的质量比电容,且具备良好的倍率性能(在10 Ag~(-1)的电流密度下仍能保持216~247 Fg~(-1)的质量比电容)和循环稳定性。最后,考察了不同升华硫用量对溶剂热法制备氮硫共掺杂碳微球的影响。在升华硫用量分别为1g、2g、3g时均可合成出氮硫共掺杂碳微球,且氮硫共掺杂碳微球的产量随升华硫剂量的增长而增长,石墨化程度随升华硫剂量的增长而减少。活化后的氮硫共掺杂碳微球在0.1 Ag~(-1)的电流密度下具备155~224 Fg~(-1)的质量比电容,具有优异的倍率性能和循环稳定性。
[Abstract]:Doped carbon microspheres, which possess excellent electrochemical properties, have great potential in supercapacitors, fuel cells, lithium ion batteries and many other fields. The preparation of sulfur and nitrogen doped carbon microspheres and its activation with KOH at high temperature by solvothermal method, transmission electron microscopy, scanning electron microscopy, N2 adsorption desorption test, Raman analysis, X ray photoelectron spectroscopy, cyclic voltammetry test, linear sweep voltammetry and galvanostatic charge test discharge test and AC impedance test analysis and characterization of the morphology, structure and electrochemical properties of the elemental composition analysis test, the results are as follows: using acetonitrile as the nitrogen source, two vulcanized four methylthiuram as sulfur source, under the temperature of 400 DEG C, after 24 h reaction, synthesis of nitrogen and sulfur codoped carbon microspheres (NS-CMSs) at different temperatures and the activation, the electrochemical test results showed that the activation temperature is at 800 DEG C NS-CMSs-800 prepared with the highest oxygen in alkaline solution is Compared with commercial 20 wt% platinum carbon catalyst, the original catalytic activity not only has four electron transfer process, but also shows better methanol tolerance and long-term stability. Nitrogen and sulfur Co doped carbon microspheres were prepared by acetonitrile as nitrogen source with sublimation sulfur, thiourea and TMTD as different sulfur sources, respectively. Nitrogen and sulfur Co doped carbon microspheres were successfully synthesized at 400 C after 16 h reaction. After the activated KOH at 750 DEG C, nitrogen and sulfur doped carbon microspheres with hierarchical pore structure, specific surface area of 397.4~413.8 m~2g~ (-1), 0.1 Ag~ (-1) of the current density, with 242~295 Fg~ (-1) mass ratio of capacitance, and have good rate capability (at 10 Ag~ (-1 216~247 Fg~) can still keep the current density (-1) of the mass specific capacitance) and cyclic stability. Finally, the effect of different sublimation sulfur content on the preparation of nitrogen and sulfur Co doped carbon microspheres by solvent heat method was investigated. The sulfur and sulfur Co doped carbon microspheres can be synthesized when the amount of sublimed sulfur is 1g, 2G and 3G respectively. The yield of nitrogen and sulfur Co doped carbon microspheres increases with the increase of sublimed sulfur dose, and the degree of graphitization decreases with the increase of sublimed sulfur dose. The activated nitrogen and sulfur Co doped carbon microspheres have 155~224 Fg~ (-1) mass ratio capacitance at 0.1 Ag~ (-1) current density, and have excellent rate performance and cycle stability.
【学位授予单位】：燕山大学
【学位级别】：硕士
【学位授予年份】：2016
【分类号】：TQ127.11

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