【作者】 李丽霞；

【导师】 宋怀河；

【作者基本信息】 北京化工大学 ， 材料学， 2007， 博士

【摘要】 有序介孔炭(ordered mesoporous carbon，OMC)不仅具有规则有序的介孔孔道、狭窄的孔径分布和高的比表面积，而且具有疏水性、化学惰性、高机械强度和高导电性，在吸附分离、催化、储能、电子电工等方面具有广泛应用前景，成为目前材料领域的研究前沿之一。针对目前普遍使用的硬模板法制备工艺繁琐、耗时长、重复性差和需要除去昂贵的表面活性剂等不足，本论文主要研究和开发了有序介孔炭的两种简单高效的合成方法，并考察了OMC的双电层电容器性能。在此基础上，制备了有序介孔炭／聚苯胺和有序介孔炭／纳米镍复合材料，分别考察了它们的超级电容器性能和磁性能。利用XRD、SEM、TEM、HRTEM、TG／DSC、FT-IR等现代分析手段研究了材料的形态结构，并与合成参数及其应用性能相关联，揭示材料制备、结构和应用性能的关系，阐明形成机理，获得系列基础研究数据。主要研究结果如下：发明有序介孔炭的两种制备方法。其一，首次通过将硫酸交联的硅／三嵌段共聚物／蔗糖复合物直接经炭化和脱硅处理成功合成出孔道排列高度有序的介孔炭。其中，三嵌段共聚物P123与蔗糖不仅作为模板剂而且共同作为碳前驱体，有效提高了炭化收率。当蔗糖：P123为1：4、晶化温度和炭化温度分别为100℃和850℃时合成了高度有序的介孔炭C-S，其最可几孔径为3.0 nm、BET比表面积为610 m~2／g、总孔体积为0.66cm~3／g。热重分析表明P123和蔗糖之间存在相互作用，C-S大约是由27wt．％的蔗糖炭和73 wt．％的P123炭组成。其二，以三种三嵌段共聚物F108、F127和P123为模板剂，采用间苯二酚／甲醛树脂为碳前驱体，首次将非水溶剂快速挥发诱导自组装技术从酸性体系发展到碱性介质中合成有序介孔炭。通过对合成条件的优化得出，当碱、F108和间苯二酚的质量比在0.3～0.5：1.5～2.5：1范围内调变时合成的介孔炭长程有序性最高。此路线从根本上摈弃了硬模板法固有的除硅过程，是目前最简便、快捷、易于大量合成的有序介孔炭的制备方法。采用恒流充放电、循环伏安和交流阻抗等电化学测试方法详细研究了具有不同孔结构的有序介孔炭与其组成的双电层电容器性能间的关系。结果表明：OMC材料均显示出理想的双电层电容行为。最可几孔径为3.6nm、比表面积为720 m~2／g的有序介孔炭C-P具有最低的阻抗和高达179F／g的比容量。尤其值得指出的是，有序介孔炭的大电流和大频率行为均好于常规活性炭，这与其具有的大而规则的孔径和高介孔率紧密相关。分别以有序介孔炭及其前驱体炭／硅复合物为基体材料，采用化学氧化法在溶液中原位合成出OMC／聚苯胺复合材料，并与物理混合法制备的复合材料在形态、结构和超级电容器性能方面开展对比研究，揭示复合材料中聚苯胺担载量、界面结合及孔结构等因素对其电容行为的影响规律。结果表明：三种复合材料的电容均由双电层电容和赝电容两部分组成。有序介孔炭与苯胺的质量比为30：70时制备的OMC／聚苯胺复合材料显示出最高的比容量(值为895 F／g)；当有序介孔炭所占比例提高到50％时，电容器的大电流和循环稳定性能达到最佳。最后，采用非水溶剂快速挥发诱导自组装技术，设计了以三嵌段共聚物F127为模板剂、六水合硝酸镍为镍前驱体，在碱性乙醇体系中原位合成OMC／纳米镍复合材料的技术路线。初步研究表明：当六水合硝酸镍与F127的质量比从0.25：2加大到0.6：2时，OMC／镍复合材料中镍粒子的粒径更均一，炭的有序性更高；当两者的质量比为0.25：2时制备的复合材料兼具铁磁和顺磁特征。更多还原

【Abstract】 Ordered mesoporous carbon （OMC） materials have attracted considerable attention for their regular mesopore arrangement, narrow pore size distribution, high specific surface area, chemical inertness and high conductivity, which may result in wide applications in the fields of adsorption, separation, catalysis, energy storage and so on.Hard template approach which was widely used to prepare OMCs has many shortages, such as a long and complicated multi-step synthetic procedure and the waste of the expensive surfactants. Therefore, in this thesis we focused on exploring the synthesis of OMCs via two simple and effective methods, and investigating the electrochemical performance of OMCs as electrode materials for supercapacitors. Besides these, two types of OMC composites （OMC/Ni and OMC/Polyaniline （PANI）） were successfully prepared, and their magnetism and supercapacitor performance were investigated, respectively. The morphologies and structures of these materials were characterized by XRD, FE-SEM, TEM, HRTEM and FT-IR measurements. The relationship among synthesis methods, structures of the derived materials and the application performances was founded, and the formation mechanism was elucidated. The main results are as follows.Two novel synthesis routes of OMCs were developed. Firstly, mesoporous carbons with highly ordered structures were successfully synthesized by the carbonization of sulfuric-acid-treated silica/triblock copolymer/sucrose composites and subsequent removal of silica. During the synthesis, triblock copolymer P123 and sucrose were employed as both template agents and carbon precursors in order to improve the carbon yield. When the mass ratio of sucrose to P123 was 1:4, crystallization temperature was 100℃and carbonization temperature was 850℃, highly ordered mesoporous carbon （C-S） with the mean pore size of 3 nm, BET specific surface area of 610 m²/g and pore volume of 0.66 cm³/g was synthesized. Thermogravimetric analysis revealed that C-S consisted of ca. 27 wt.% sucrose carbon and ca. 73 wt.% P123 carbon, and there was noticeable interaction between sucrose and P123. Secondly, the evaporation-induced self-assembly （EISA） technique was developed to synthesize a series of OMCs in alkali media by use of triblock copolymers F108, F127 or P123 as template agent and resorcin/formaldehyde resin （RFR） as carbon precursor. By optimizing the synthesis conditions, it was concluded that mesoporous carbons with highly ordered pores were prepared when the mass ratio of alkali, F108 and resorcin was in the range of 0.3～0.5:1.5～2.5:1. This route, avoiding the use of hard silica template, possesses the advantages of simplicity, effectivity and low cost, and will be a most promising approach for the large-scale synthesis of OMCs.The relationship between electrochemical performance of OMCs as electrode materials for electric double-layer capacitors and their pore characteristics was elucidated by using galvanostatic charge-discharge test, cyclic voltammetry and impedance spectroscopy. It was found that all of OMCs exhibited the ideal double-layer capacitance behaviors. The material C-P exhibited the lowest resistance and highest specific capacitance value of 179 F/g, which can be attributed to its high specific surface area of 720 m²/g and pore size distribution centered at 3.6 nm. In addition, the noteworthy is that the capacitance maintenance at high current load and high-frequency capacitive performance of OMCs were better than those of the general activated carbons, wherein larger mesopores and high mesopore fraction played important roles.OMC or its precursor （carbon/silica composite） was used as body material to prepare OMC/PANI composites via in-situ polymerization method. Compared with OMC/PANI composites prepared via physical mixing method, the researches on the materials’ configurations, structures and supercapacitor performances were developed, and the influence of the content of PANI, interface combination and pore structure on capacitance behaviors was deduced. It is inferred that, regardless of the synthesis method, composites’ capacitances consisted of double layer capacitance and redox capacitance. When the mass ratio of OMC to aniline was 30:70, the OMC/PANI composite prepared by in-situ polymerization method exhibited highest special capacitance of 895 F/g. When their mass ratio was increased to 50:50, the outstanding high rate capability was obtained.Finally, EISA was developed to synthesize OMC/Ni composite in alkali ethanol by using F127 as template agent and Ni（NO₃）₂·6H₂O as nickel source. It is deduced that the nickel particles in composite prepared by increasing the mass ratio of Ni（NO₃）₂·6H₂O and F127 from 0.25:2 to 0.6:2 were dispersed more uniformly and the pores of carbon were more ordered. When their mass ratio was 0.25:2, the composites exhibited the combined characteristics of ferromagnetism and paramagnetism.更多还原