超级电容器用煤液化残渣基亚微米级多孔炭纤维无纺布制备及结构调控

Coal liquefaction residue (CLR) was extracted by different solvent fractionation, and extraction products with different molecular composition were used as the carbon source for preparation of porous carbon sub-micro fiber non-woven fabrics. Spinning solution was prepared by blending the extraction products , fiber-forming polymer, pore forming agent and conductive additives, and CLR-based porous carbon sub-micro fiber non-woven fabrics were produced by electrospinning, carbonization and activation from the spinning solution in the project. The evolution of structure, the mechanism of electrical conductivity and the formation mechanism of pore structure of the product during the process were elucidated, and the correlation between the structure and the electrochemical properties of porous carbon sub-micro fiber non-woven fabrics were clearly recognized. Finally, CLR-based porous carbon sub-micro fiber non-woven fabric with a hierarchical porous structure was prepared successfully. The BET surface area of the product was bigger than 1000m2/g, and the capacitance was larger than 200F/g at the current density of 10A/g. Through the research of this project, it can realize the high efficiency and high value utilization of coal, improve the preparation of coal-based carbon materials, provide high performance flexible carbon electrode material for supercapacitor, and provide theoretical support for the development and application of new energy storage devices such as supercapacitor.

本项目拟通过将煤炭液化残渣（CLR）进行溶剂分级萃取后，利用不同分子组成的萃取物与成纤聚合物、造孔剂和导电添加剂共混制备纺丝原液，经静电纺丝、不熔化、炭/活化处理等制备CLR基亚微米级多孔炭纤维无纺布。阐明电纺、不熔化、炭化等过程产物的结构演变、导电性提升机理和孔结构形成机理，认清亚微米级多孔炭纤维结构与其电化学性能之间的相关性。最终制得比表面积大于1000m2/g、在10A/g的电流密度下比电容大于200F/g的具有层次孔结构、高导电性的超级电容器电极用CLR基柔性亚微米级多孔炭纤维无纺布。通过该项目的研究，不仅可以实现煤炭液化过程中废弃物的循环再利用，丰富煤基炭材料的制备科学，为超级电容器提供高性能柔性炭电极材料，而且对超级电容器等新型储能器件的开发和实用化提供理论支撑。

煤液化技术是实现煤炭资源清洁高效利用的有效途径之一，但煤直接液化在获得液体燃料的同时，还产生占原煤总量约30%的主要副产物---液化残渣（CLR）。高效合理利用CLR对液化过程的资源利用率和经济性有着不可低估的影响，是完善煤直接液化技术的一个重要课题。CLR中的沥青烯和前沥青烯分子均主要由C元素组成，基本结构单元中是以多个芳环组成的稠和芳环为核心，芳环周围连接有若干个长度不一的烷基侧链或者环烷环，芳香度高，碳含量高，容易发生聚合或者交联，适宜作为制备炭材料的前驱体。本项目通过将CLR进行溶剂分级萃取后，选用适宜于制备炭材料的沥青烯和前沥青烯为碳源，以聚丙烯腈为助纺剂，通过静电纺丝、不熔化和炭化处理等制备了CLR基纳米炭纤维无纺布。通过调控纺丝原液配比、电纺条件、不熔化和炭化条件成功制备得到了具有较好柔韧性的纳米炭纤维无纺布，采用硝酸预处理结合空气不熔化、纺丝原液中添加苯甲酸等方法有效解决了不熔化过程中纤维间的融并现象。阐明了电纺、不熔化、炭化等过程产物的结构和形貌演变规律，以及多孔纳米炭纤维无纺布结构与其电化学性能之间的相关性。最终制得了比表面积高、电化学性能好(尤其是大电流密度下倍率性能高）的超级电容器电极用CLR基柔性多孔纳米炭纤维无纺布。通过该项目的研究，实现了煤液化过程中废弃物的循环再利用，丰富了煤基炭材料的制备科学，为超级电容器提供了高性能柔性炭电极材料，而且对超级电容器等新型储能器件的开发和实用化提供了理论支撑。项目研究成果不仅具有较好的学术价值，而且具有较高的应用价值和社会影响力。