以褐煤、煤系腐植酸和煤沥青为原料,聚丙烯腈为助纺剂,三苯基膦为掺杂剂,采用静电纺丝法制备出磷掺杂煤基碳纤维,重点研究磷原子掺杂对煤基碳纤维微观结构和表面特性的影响。研究表明,褐煤、煤系腐植酸和煤沥青经静电纺丝法可成功制备出具有良好柔性的磷掺杂煤基碳纤维。所制备的磷掺杂煤沥青基碳纤维P-CTP-CFs相互交织形成三维网状结构,其平均直径为144.0nm,比表面积为50.3m2/g,同时含有大量无定形碳和C—O、C=O、O—C=O、吡啶氮、吡咯氮、石墨氮及P—C/P—N、P—O、P=O等杂原子官能团。磷掺杂煤沥青基碳纤维P-CTP-CFs用作锂离子电池自支撑负极材料时具有优异的电化学性能,在20mA/g的电流密度下,可逆容量达到944.9mAh/g,在1000mA/g大电流密度下可逆容量仍有273.6mAh/g。且在100mA/g的电流密度下,经过100次循环后可逆容量保持率可达到86.2%,显示出良好的倍率性能和优异的循环稳定性,是一种较为理想的锂离子电池柔性负极材料。磷掺杂煤沥青基碳纤维优异的储锂特性与其特殊的三维网状结构、较大的比表面积和丰富的杂原子官能团密切相关。

Phosphorus-doped coal-based carbon fibers were prepared by electrostatic spinning method using lignite,coal humic acid andcoal pitch as raw materials,polyacrylonitrile as spinning aid and triphenylphosphine as dopant,focusing on the effect of phosphorusatomic doping on the microstructure and surface properties of coal-based carbon fibers. It was shown that phosphorus-doped coal-basedcarbon fibers with good flexibility could be successfully prepared from lignite,coal humic acid and coal pitch by electrostatic spinningmethod. The prepared phosphorus-doped coal pitch-based carbon fibers P-CTP-CFs were interwoven with each other to form a three-dimensional mesh structure with an average diameter of 144.0 nm and a specific surface area of 50.3 m/g,and also contained a largeamount of amorphous carbon and heteroatomic functional groups such as C—O,C=O,O—C=O,pyridinic nitrogen,pyrrolic nitrogen,graphitic nitrogen,and P—C/P—N,P—O,P=O. When used as self-supporting anode materials for lithium-ion batteries (LIBs),P-CTP-CFs have excellent electrochemical properties,with a reversible capacity of 944.9 mAh/g at a current density of 20 mA/g,and areversible capacity of 273.6 mAh/g at a high current density of 1000 mA/g,and the reversible capacity can be maintained at 86.2% after 100 cycles at a current density of 100 mA/g,showing good multiplicity performance and excellent cycling stability,which is a more idealflexible anode material for LIBs. The excellent lithium storage properties of phosphorus-doped coal pitch-based carbon fibers are closelyrelated to their special three-dimensional mesh structure,large specific surface area and abundant heteroatomic functional groups.