A series of flexible and self-standing coal-derived carbon fibers(CCFs)were fabricated through electro-spinning coupled with carbonization using bituminous coal and polyacrylonitrile(PAN)as the carbon precursors.These...A series of flexible and self-standing coal-derived carbon fibers(CCFs)were fabricated through electro-spinning coupled with carbonization using bituminous coal and polyacrylonitrile(PAN)as the carbon precursors.These CCFs were utilized as free-standing lithium-ion battery(LIB)anodes.Optimizing car-bonization temperature reveals that the CCFs exhibit a one-dimensional solid linear structure with a uni-form distribution of graphite-like microcrystals.These fibers possess a dense structure and smooth surface,with averaging diameter from approximately 125.0 to 210.0 nm at carbonization temperatures ranging from 600 to 900℃.During electrospinning and carbonization,the aromatic rings enriched in bituminous coal crosslink with PAN chains,forming a robust three-dimensional(3D)framework.This 3D microstructure significantly enhances the flexibility and tensile strength of CCFs,while increasing the graphite-like sp^(2)microcrystalline carbon content,thus improving electrical conductivity.The CCFs carbonized at 700℃demonstrate an optimal balance of sp^(3)amorphous and sp^(2)graphite-like carbons.The average diameter of CCFs-700 is 177 nm and the specific surface area(SSA)is 7.2 m^(2)g^(-1).Additionally,the fibers contain oxygen-containing functional groups,as well as nitrogen-containing func-tional groups,including pyridinic nitrogen and pyrrolic nitrogen.Owing to its characteristics,the CCFs-700 showcases remarkable electrochemical performance,delivering a high reversible capacity of 631.4 mAh g^(-1).CCFs-700 also exhibit outstanding cycle stability,which retains approximately all of their first capacity(400.1 mAh g^(-1))after 120 cycles.This research offers an economical yet scalable approach for producing flexible and self-supporting anodes for LIBs that do not require current collectors,binders and conductive additives,thereby simplifying the electrode fabrication process.展开更多
基金supported by the National Natural Science Foundation of China(Nos.52474290,52274261,52074109,52304284)the Open Subjects of Henan Provincial Key Laboratory of Coal Green Conversion(No.CGCF202201)+1 种基金the Key Scientific and Technological Project of Henan Province(No.242102240008)the Key Scientific Research Projects of Colleges and Universities in Henan Province(No.24A440003).
文摘A series of flexible and self-standing coal-derived carbon fibers(CCFs)were fabricated through electro-spinning coupled with carbonization using bituminous coal and polyacrylonitrile(PAN)as the carbon precursors.These CCFs were utilized as free-standing lithium-ion battery(LIB)anodes.Optimizing car-bonization temperature reveals that the CCFs exhibit a one-dimensional solid linear structure with a uni-form distribution of graphite-like microcrystals.These fibers possess a dense structure and smooth surface,with averaging diameter from approximately 125.0 to 210.0 nm at carbonization temperatures ranging from 600 to 900℃.During electrospinning and carbonization,the aromatic rings enriched in bituminous coal crosslink with PAN chains,forming a robust three-dimensional(3D)framework.This 3D microstructure significantly enhances the flexibility and tensile strength of CCFs,while increasing the graphite-like sp^(2)microcrystalline carbon content,thus improving electrical conductivity.The CCFs carbonized at 700℃demonstrate an optimal balance of sp^(3)amorphous and sp^(2)graphite-like carbons.The average diameter of CCFs-700 is 177 nm and the specific surface area(SSA)is 7.2 m^(2)g^(-1).Additionally,the fibers contain oxygen-containing functional groups,as well as nitrogen-containing func-tional groups,including pyridinic nitrogen and pyrrolic nitrogen.Owing to its characteristics,the CCFs-700 showcases remarkable electrochemical performance,delivering a high reversible capacity of 631.4 mAh g^(-1).CCFs-700 also exhibit outstanding cycle stability,which retains approximately all of their first capacity(400.1 mAh g^(-1))after 120 cycles.This research offers an economical yet scalable approach for producing flexible and self-supporting anodes for LIBs that do not require current collectors,binders and conductive additives,thereby simplifying the electrode fabrication process.