Abstract：Carbon nanofibers with various contents of Co nanoparticle were synthesized by a two step process of electrospinning and subsequent heat treatment. The thermal stability,phase composition,microstructure and electromagnetic characteristics of the carbon nanofibers were characterized by differential scanning calorimetry-thermogravimmetric analysis (DSC-TGA),X-ray diffraction(XRD),scanning electron microscope(SEM) and vector network analyzer(VNA),and the microwave absorption performance was studied.The results indicate that the crystallinity of composite nanofibers is moderate when the carbonization temperature is 800℃.The amorphous carbon is partially converted into graphite and CoAc2 completely reduces to face-centered cubic structured Co nanoparticle. The fiber is intact and beads-on-string structure exists in the fiber networks. The electromagnetic characteristics of the carbon nanofibers significantly improve by the doping of Co. The Carbon nanofibers containing 7%(mass fraction) as fillers with thickness of 1.5mm exhibit maximum effective absorption bandwidth of 4.5GHz, and it is obviously improved compared to pure carbon nanofibers.
张飒, 王建江, 赵芳, 刘嘉玮. 电纺Co掺杂碳纳米纤维的制备及其吸波性能[J]. 材料工程, 2019, 47(12): 118-123.
ZHANG Sa, WANG Jian-jiang, ZHAO Fang, LIU Jia-wei. Preparation of Co doped carbon nanofibers composites synthesized by electrospinning and its microwave absorption properties. Journal of Materials Engineering, 2019, 47(12): 118-123.
 LI M Q,HU Y M,FANG J H,et al.Current status and future trends of electromagnetic-wave absorbent with nano-structure[J].Materials Review,2002,16(9):15-17.
 SUN G B,DONG B X,CAO M H,et al.Hierarchical dendrite-like magnetic materials of Fe3O4, γ-Fe2O3, and Fe with high performance of microwave absorption[J].Chemistry of Materials,2011,23:1587-1593.
 MURAKAMI R I,YAMAMOTO H,KIM C K,et al.Electromagnetic wave shielding effectiveness of carbon fiber sheet coated ferrite film by micowave-hydrothermal process[J].International Journal of Modern Physics B,2003,17:8-9.
 ZENG J,XU J C. Microwave absorption properties of CuO/Co/carbon fiber composites synthesized by thermal oxidation[J].Journal of Alloys and Compounds,2010,493:L39-L41.
 WANG L,HE F,WAN Y Z.Facile synthesis and electromagnetic wave absorption properties of magnetic carbon fiber coated with Fe-Co alloy by electroplating[J].Journal of Alloys and Compounds,2011,509:4726-4730.
 LIU X G,GENG D Y,MENG H,et al.Microwave absorption properties of FCC-Co/Al2O3 and FCC-Co/Y2O3 nanocapsules[J].Solid State Communications,2009,149:64-67.
 LIN H Y,ZHU H,GUO H F,et al.Microwave-absorbing proper of Co-filled carbon nanotubes[J]. Materials Research Bulletin,2008,43:2697-2702.
 TABATABAIE F,FATHI M H,SAATCHI A.Effect of Mn-Co and Co-Ti substituted ions on doped strontium ferrites microwave absorption[J].Journal of Alloys and Compounds,2009,474:206-209.
 张克力,贾漫珂,汤昊,等.乙酸钴热分解机理研究[J].武汉大学学报(理学版),2002,48(4):409-412. ZHANG K L,JIA M K,TANG H,et al.The thermal decomposition mechanism of cobaltous acetate[J].Journal of Wuhan University(Natural Science Edition),2002,48(4):409-412.
 PENG J,CHEN N,HE R,et al.Electrochemically driven transformation of amorphous carbons to crystalline graphite nanoflakes:a facile and mild graphitization method[J].Angewandte Chemie International Edition,2017,56(7):1751-1755.
 LI G M,ZHU B S,LIANG L P,et al.Core-shell Co3Fe7@C composite as efficient microwave absorbent[J].Acta Physico-Chimica Sinica,2017,33(8):1715-1720.
 Mc CLURE J P,JIANG R Z,CHU D Y,et al.Oxygen electroreduction on Fe or Co-containing carbon fibers[J].Carbon,2014,79:457-469.
 PUNTES V F,KRISHAN K M,ALIVISATUS A P.Colloidal nanocrystal shape and size control:the case of cobalt[J].Science,2001,291(5511):2115-2121.
 高大伟,王丽丽,陆振乾,等.金属掺杂对碳纳米纤维结构及导电性能的研究[J]. 材料导报,2015,29(22):87-90. GAO D W,WANG L L,LU Z Q,et al.Study on the effects of metal-doping on the structure and conductivity of carbon nanofibers[J]. Materials Reports,2015,29(22):87-90.
 CAO M S,YANG J,SONG W L,et al.Ferroferric oxide/multiwalled carbon nanotube vs polyaniline/ferroferric oxide/multiwalled carbon nanotube multiheterostructures for highly effective microwave absorption[J].ACS Applied Materials & Interfaces,2012,4(12):6949-6956.
 向军,张雄辉,叶芹,等.Fe-Ni/C复合纳米纤维的原位制备与微波吸收性能[J].高等学校化学学报,2014,35(7):1379-1387. XIANG J,ZHANG X H,YE Q,et al.Fe-Ni/C in-situ preparation and microwave absorbing properties of composite nano-fibers[J].Chemical Journal of Chinese Universities,2014,35(7):1379-1387.
 王晓磊,包秀坤,关银燕,等.C/Co核壳亚微米复合物的吸波性能[J].材料研究学报,2017,31(4):241-247. WANG X L,BAO X K,GUAN Y Y,et al.Microwave absorption properties of submicro-composites of core-shell C/Co[J].Chinese Journal of Materials Research,2017,31(4):241-247.
 LIU J W,CHE R C,CHEN H J,et al.Microwave absorption enhancement of multifunctional composite microspheres with spinel Fe3O4 cores and anatase TiO2 shells[J].Small,2012,8(8):1214-1221.
 DING D H,ZHOU W C,ZHANG B.Complex permittivity and microwave absorbing properties of SiC fiber woven fabrics[J]. Journal Materials Science,2011,46:2709-2714.
 WANG B C,WEI J Q,YANG Y,et al.Investigation on peak frequency of the microwave absorption for carbonyliron/epoxy resin composite[J].Journal of Magnetism and Magnetic Materials,2011,23(8):1101-1103.
 LI G,XIE T S,YANG S L,et al.Microwave absorption enhancement of porous carbon fibers compared with carbon nanofibers[J]. The Journal of Physical Chemistry C,2012,116(16):9196-9201.