采用催化化学气相沉积法在微米硅颗粒表面原位生长纳米炭纤维得到纳米炭纤维/硅复合材料.利用SEM,TEM和XRD表征了复合材料的表面形态和微观结构,并考察了其作为锂离子电池负极材料的循环性能.电化学测试表明:与纳米纤维/硅机械混合物相比,原位生长纳米炭纤维/硅复合材料具有更高的可逆容量(1042mAh/g)和更好的循环稳定性.根据SEM和交流阻抗分析结果,分析了纳米炭纤维/硅复合材料在充放电过程中的结构演变机制,其优异的电化学性能主要来源于原位生长纳米炭纤维与硅颗粒之间良好的接触性能.
A CNF/Si composite was synthesized in situ by growing carbon nanofibers on the surface of silicon particles through catalytic chemical vapor deposition. Microstructures of the composites were characterized by scanning and trans-mission electron microscopy, and X-ray diffraction. Electrochemical measurements indicated that the composite showed higher reversible capacity (1042mAh/g) and better cyclability than did a CNF-Si mixture prepared by simple mechanical milling. A structural evolution mechanism is proposed to explain the superior electrochemical performance of the CNF/Si composite electrode in comparison with the CNF-Si mixture. Scanning electron microscopy and ac impedance analysis in-dicated that the electrochemical performance can be attributed to the good contact of the in situ grown carbon fiber with the silicon particles.
参考文献
[1] | Huggins R A .Lithium ailoy negative electrodes[J].Journal of Power Sources,1999,81-82:13-19. |
[2] | Winter M;Besenhard J O .Electrochemical lithiation of tin and Dtin-based intermetallics and composites[J].Electrochimica Acta,1999,45:31-50. |
[3] | Uday Kasavajjula;Chunsheng Wang;A. John Appleby .Nano- and bulk-silicon-based insertion anodes for lithium-ion secondary cells[J].Journal of Power Sources,2007(2):1003-1039. |
[4] | Sharma R A;Seefurth R N .Thermodynanaic properties of the lithium-silicon system[J].Journal of the Electrochemical Society,1976,123:1763-1768. |
[5] | Wang GX;Ahn JH;Yao J;Bewlay S;Liu HK .Nanostructured Si-C composite anodes for lithium-ion batteries[J].Electrochemistry communications,2004(7):689-692. |
[6] | Chew SY;Guo ZP;Wang JZ;Chen J;Munroe P;Ng SH;Zhao L;Liu HK .Novel nano-silicon/polypyrrole composites for lithium storage[J].Electrochemistry communications,2007(5):941-946. |
[7] | Obrovac MN;Krause LJ .Reversible cycling of crystalline silicon powder[J].Journal of the Electrochemical Society,2007(2):A103-A108. |
[8] | Li J;Dohn J R .An in situ X-ray diffraction study of the reation of Li with crystalline Si[J].Journal of the Electrochemical Society,2007,154:A156-A161. |
[9] | Morita T;Takami N .Nano Si cluster-SiOx-C composite material as high capacity anode materiai for rechargeable lithium batteries[J].Journal of the Electrochemical Society,2006,153:A425-A430. |
[10] | Yang X L;Wen Z Y;Xu X X et al.High performance silicon/carbon/graphite composite as anode materials for lithium ion batteries[J].Journal of the Electrochemical Society,2006,153:A1341-A1344. |
[11] | Volodymyr G. Khomenko;Viacheslav Z. Barsukov .Characterization of silicon- and carbon-based composite anodes for lithium-ion batteries[J].Electrochimica Acta,2007(8):2829-2840. |
[12] | Eom J Y;Park J W;Kwon H S et al.Electrochemical insetion of lithium into mutiwalled carbon nanotube/silicon composites produce by ballmilling[J].Journal of the Electrochemical Society,2006,153:A1678-A1684. |
[13] | See-How Ng;Jiazhao Wang;David Wexler;Konstantin Konstantinov;Zai-Ping Guo;Hua-Kun Liu .Highly Reversible Lithium Storage in Spheroidal Carbon-Coated Silicon Nanocomposites as Anodes for Lithium-Ion Batteries[J].Angewandte Chemie,2006(41):6896-6899. |
[14] | Dimov N;Kugino S;Ysohio M .Carbon-coated silicon as anode material for lithium ion batteries:advantages and limitations[J].Electrochimica Acta,2003,48:1579-1587. |
[15] | 赵建国,刘朗,郭全贵,史景利,翟更太,宋进仁.炭纤维表面生长碳纳米管[J].新型炭材料,2008(01):12-16. |
[16] | Yoon S H;Park C W;Yang H J et al.Novel carbon nanofibets of high graphitization as anodic materials for lithium ion secondary batteries[J].CARBON,2004,42:31-32. |
[17] | Hao Sun;Xiangming He;Jianguo Ren;Jianjun Li;Changyin Jiang;Chunrong Wan .Hard carbon/lithium composite anode materials for Li-ion batteries[J].Electrochimica Acta,2007(13):4312-4316. |
[18] | Dimov N;Kugino S;Yoshio M .Mixed silicon-graphite composite as anode material for lithium ion batteries:Influence of preparation conditions on the properties of the material[J].Journal of Power Sources,2004,136:108-114. |
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