摘要
煤沥青因其来源广泛、碳含量高和高度芳香化等被认为是制备石墨化多孔炭的优良前驱体,然而煤沥青具有显著的热塑性特征,为基于其制备的碳电极材料的孔结构调控带来了显著挑战。因此,采用煤沥青四氢呋喃可溶物与聚丙烯腈混合物为前驱体,经静电纺丝、预氧化和活化-炭化共处理后,制备煤沥青衍生多孔碳纤维,系统研究了活化工艺(活化剂浓度、活化温度)对材料结构和性能的影响。结果表明:活化工艺能有效平衡材料的比表面积和石墨化程度,其中活化剂浓度为3 mol/L,活化温度为800℃时制备的煤沥青衍生多孔碳纤维(A_(3)PCNF-800)具有1 627.2 m^(2)/g的比表面积和较高的无序度(I_(D)/I_(G)=1.09),其在0.5 A/g电流密度下表现出254.5 F/g的比电容,当电流密度提升到5 A/g时,样品的容量保持率可达84.7%。将其组装为对称式超级电容器后,在162.5 W/kg功率密度下能量密度最高可达16.6 Wh/kg,且在5 A/g下循环10 000次后电容保持率和库仑效率能分别达到97.05%和98.95%。
Coal pitch,due to its wide availability,high carbon content,and high degree of aromatization,is considered an excellent precursor for the preparation of graphitized porous carbon.However,its significant thermoplastic characteristics poses challenges for pore structure regulation carbon electrode fabrication.In this study,coal pitch tetrahydrofuran-soluble fractions and polyacrylonitrile(PAN)blends were used as precursors to prepare coal pitch-derived porous carbon fibers via electrospinning,pre-oxidation,and coactivation-carbonization treatment.The effects of the activation process—including activator concentration and activation temperature—on the structure and electrochemical performance of the materials were systematically investigated.The results show that the activation process can effectively balance the specific surface area and the degree of graphitization of the resulting materials.In particular,the coal pitch-derived porous carbon fiber(A3PCNF-800),prepared at an activator concentration of 3 mol/L and an activation temperature of 800℃,exhibits a specific surface area of 1627.2 m2/g and a high degree of disorder(ID/IG=1.09).This sample delivers a specific capacitance of 254.5 F/g at a current density of 0.5 A/g,and maintained 84.7%of its capacitance when the current density increases to 5 A/g.When assembled into a symmetric supercapacitor,the device achieves a maximum energy density of 16.56 Wh/kg at a power density of 162.5 W/kg,with capacitance retention and Coulombic efficiency reaching 97.05%and 98.95%,respectively,after 10000 charge-discharge cycles at 5 A/g.
作者
曹亚敏
赵佳辉
岳鲁超
王建成
米杰
冯宇
CAO Yamin;ZHAO Jiahui;YUE Luchao;WANG Jiancheng;MI Jie;FENG Yu(College of Chemistry and Chemical Engineering,State Key Laboratory of Clean and Efficient Coal Utilization,Taiyuan University of Technology,030024 Taiyuan,China;School of Chemistry and Chemical Engineering,North University of China,030051 Taiyuan,China)
出处
《煤炭转化》
北大核心
2025年第4期26-36,共11页
Coal Conversion
基金
国家自然科学基金资助项目(22378292,21908156)
山西省应用基础研究计划项目(202403021224005,202303021211072)。
关键词
煤沥青
超级电容器
多孔炭
电化学性能
coal pitch
supercapacitor
porous carbon
electrochemical performance
