Wang Shuxian, Huang Chunlai, Wang Lei, Sun Wei, Yang Deren
State Key Laboratory of Silicon Materials, School of Materials Science and Engineering, Zhejiang University Hangzhou 310027 P. R. China
Jiangsu Key Lab of Silicon Based Electronic Materials, Jiangsu GCL Silicon Material Technology Development Co., Ltd. Xuzhou 221000 P. R. China.
RSC Adv. 2018 Dec 7;8(71):41101-41108. doi: 10.1039/c8ra07483f. eCollection 2018 Dec 4.
Herein, we present a simple and rapid method to synthesize porous silicon/carbon microtube composites (PoSi/CMTs) by adopting a unique configuration of acid etching solution. The CMTs can act as both conductive agent and buffer for Si volume change during the charge and discharge process. The highly reversible capacity and excellent rate capability can be ascribed to the structure, where porous silicon powders are wrapped by a network of interwoven carbon microtubes. The composites show specific capacities of more than 1712 mA h g at a current density of 100 mA g, 1566 mA h g at 200 mA g, 1407 mA h g at 400 mA g, 1177 mA h g at 800 mA g, 1107 mA h g at 1000 mA g, 798 mA hg at 2000 mA g, and 581 mA h g at 3000 mA g and maintain a value of 1127 mA h g after 100 cycles at a current density of 200 mA g. Electrochemical impedance spectroscopy (EIS) measurements prove that charge transfer resistance of PoSi/CMT composites is smaller than that of pure PoSi. In this study, we propose a quick, economical and feasible method to prepare silicon-based anode materials for lithium-ion batteries.
在此，我们提出一种简单快速的方法，通过采用独特配置的酸蚀刻溶液来合成多孔硅/碳微管复合材料（PoSi/CMTs）。CMTs在充放电过程中既可以作为导电剂，又可以作为硅体积变化的缓冲剂。高可逆容量和优异的倍率性能可归因于该结构，其中多孔硅粉末被交织的碳微管网络包裹。该复合材料在100 mA g的电流密度下比容量超过1712 mA h g，在200 mA g时为1566 mA h g，在400 mA g时为1407 mA h g，在800 mA g时为1177 mA h g，在1000 mA g时为1107 mA h g，在2000 mA g时为798 mA h g，在3000 mA g时为581 mA h g，并且在200 mA g的电流密度下循环100次后保持1127 mA h g的值。电化学阻抗谱（EIS）测量证明PoSi/CMT复合材料的电荷转移电阻小于纯PoSi的电荷转移电阻。在本研究中，我们提出了一种快速、经济且可行的方法来制备锂离子电池的硅基负极材料。
