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有序中孔炭的制备及其电化学性能

更新时间 2009-9-12 10:46:22 点击数:

有序中孔炭的制备及其电化学性能
Ordered Mesoporous Carbons: Preparation and Capacitance Properties
【中文摘要】 以煤炭液化副产物沥青烯(A)、预沥青烯(P)、及沥青烯与预沥青烯的混合物(M)为碳源,SBA-15为模板,采用模板法制备了有序中孔炭材料OMC-A、OMC-P及OMC-M。采用透射电镜、X射线衍射、物理吸附等技术手段对产品的微观形貌和结构进行了分析;在电化学工作站上测定了产品炭作为电极材料组装电容器的电化学性能;探讨了产品炭结构与其电化学性能的关系。结果表明以三种碳源为原料制得的中孔炭产品均为模板结构的反复制体,孔结构高度有序,具有较高的比表面积及比孔容,比表面积为542~843m2·g-1,比孔容为0.5~0.7cm3·g-1。由三种产品中孔炭作为电极材料组装成超级电容器进行电化学性能测试,结果显示均具有良好的电化学性能,在电解质为6mol·L-1的KOH溶液的三电极体系下,1mA的电流强度时,单电极质量比电容值均高于300F·g-1,其中OMC-M的比电容值最高,达到413F·g-1。通过调节模板合成条件,制备了具有不同孔尺寸的模板剂,并由此制得孔尺寸不同的炭材料,考察了规则结构中孔炭的孔径尺寸对电化学性能的影响;改变炭化终温制备了具有不同石墨化程度的中孔炭材料,考察了石墨化对电化学性能的影响。结果表明,材料的比表面积、孔道排列方式、石墨化程度和孔尺寸均为影响炭材料电化学性能的重要因素,在本文研究条件下,高比表面积有益于电容器比电容的提高,比电容值随比表面积的增加而增加;孔排列有序度高,比表面积利用率高,有利于得到较高比电容值;石墨化程度的提高有利于电容器体系产生理想的电容行为;中孔炭材料孔径在4nm时具有较高的比电容。

【英文摘要】 Asphaltene(A),preasphaltene(P),and the mixture of asphaltene and preasphaltene(M) extracted from coal liquefaction residue were taken as carbon precursors to synthesize ordered mesoporous carbons(OMCs).The OMCs of OMC-A,OMC-P and OMC-M were synthesized by template method,using SBA-15 as template.The microstructures of the carbons were studied by X-ray diffraction(XRD),transmission electron microscopy(TEM), and N2 adsorption.Electrochemical workstation was used to analyse the electrochemical characteristics of the capacitors assembled from the OMCs.The effect of pore structure on capacitance properties was discussed.The results show that the OMCs are all reverse replications of the template,and have highly ordered pore structures.The carbons have high specific surface areas and pore volumes,which range from 542~843m2·g-1 and 0.5~0.7cm3·g-1,respectively.The electrochemical characteristics of the capacitors from the OMCs were studied with 6mol·L-1 KOH as electrolyte in three-electrode system.The results indicate the excellent capacitance properties of the OMCs,of which the specific capacitances are above 300F·g-1 at the current intensity of 1mA.Among them OMC-M is as high as 413F·g-1.Ordered mesoporous carbons with different pore diameters were prepared by taking templates with various pore sizes,and the effect of pore size on capacitance properties was studied.Ordered mesoporous carbons with different graphitization degrees were produced by adjusting carbonization temperature and the impact of graphitization degree on capacitance properties was investigated.The results show all the specific surface areas,orderliness of pores,graphitization degrees,and pore sizes of the carbons have significant influence on their electrochemical characteristics:the specific capacitances were incrseased with the increase of the specific surface area;highly ordered pore structure leads to increasing utilizationon of specific surface area,which is benefical to improve specific capacitance;the increase of the graphitization degree results in the ideal electric double layer behavior;under the research conditions in this paper,the OMCs with pore diameter of 4nm have higher capacitances.

【中文关键词】 沥青烯; 预沥青烯; 中孔炭; 模板法; 比电容
【英文关键词】 Asphaltene; preasphaltene; mesoporous carbon; template method; capacitance
毕业论文目录】
摘要 4-5
Abstract 5
引言 8-9
1 文献综述 9-25
    1.1 沥青烯、预沥青烯 9-12
        1.1.1 沥青烯及预沥青烯的组成、结构和性质 9-11
        1.1.2 沥青烯、预沥青烯的应用 11-12
    1.2 中孔炭的研究进展 12-23
        1.2.1 中孔炭的制备方法 13-20
        1.2.2 中孔炭的性质及其应用 20-22
        1.2.3 中孔炭的电化学性质及其在超级电容器领域的应用 22-23
    1.3 本课题的研究目的及意义 23-25
2 基于沥青烯、预沥青烯的中孔炭的制备 25-34
    2.1 实验部分 25-29
        2.1.1 实验原料及设备 25-28
        2.1.2 沥青烯、预沥青烯及其混合物的提取 28
        2.1.3 中孔炭的合成方法 28-29
        2.1.4 产品的表征 29
    2.2 结果与讨论 29-34
        2.2.1 XRD分析 29-30
        2.2.2 TEM分析 30
        2.2.3 N_2吸附分析 30-33
        2.2.4 小结 33-34
3 产品中孔炭的电化学性能 34-42
    3.1 实验部分 34-35
        3.1.1 实验原料及设备 34-35
        3.1.2 电极的制备 35
        3.1.3 产品的电化学性能测试 35
    3.2 结果与讨论 35-42
        3.2.1 循环伏安测试 35-37
        3.2.2 恒流充放电测试 37-40
        3.2.3 交流阻抗谱测试 40-41
        3.2.4 小结 41-42
4 中孔炭结构对其电化学性能的影响 42-55
    4.1 实验部分 42-43
        4.1.1 实验原料及设备 42
        4.1.2 中孔炭的合成 42-43
        4.1.3 电极的制备 43
        4.1.4 产品的表征 43
    4.2 结果与讨论 43-55
        4.2.1 中孔炭的结构特征 43-47
        4.2.2 中孔炭的电化学性能 47-53
        4.2.3 小结 53-55
5 炭化终温对中孔炭电化学性能的影响 55-65
    5.1 实验部分 55
        5.1.1 实验原料及设备 55
        5.1.2 中孔炭的合成 55
        5.1.3 电极的制备 55
        5.1.4 产品的表征 55
    5.2 结果与讨论 55-65
        5.2.1 中孔炭的结构特征 55-60
        5.2.2 中孔炭的电化学性能 60-63
        5.2.3 小结 63-65
结论 65-66
参考文献 66-73
攻读硕士学位期间发表学术论文情况 73-74
致谢 74-75

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