Fe_(3)O_(4)/CNTs纳米复合材料的制备及其电化学性能的研究

Preparation of Fe_(3)O_(4)/CNTs Nanocomposite and Their Electrochemical Performance as Anode Materials for Lithium Ion Batteries

Fe_(3)O_(4)/CNTs纳米复合材料用水热法在乙醇和丙二醇的混合溶液中合成,尺寸为5~15 nm的四氧化三铁纳米颗粒均匀附着在碳纳米管表面。作为锂电池负极材料,合成的Fe_(3)O_(4)/CNTs纳米复合材料展现出了优异的长循环特性和倍率循环特性。在电流密度100 mA g^(-1)的条件下,在300次循环充放电后容量仍然能够保持在605 mAh g^(-1)。酸处理碳纳米管的加入为四氧化三铁提供了大量的生长点,显著减小了四氧化三铁颗粒的尺寸,阻止了充放电过程中颗粒的团聚,构建了独特的三维导电网,使复合材料展现出了优异的电化学性能。

In this work,Fe_(3)O_(4)/CNTs nanocomposite with well-distributed Fe_(3)O_(4) nanoparticles of 5~15 nm has been fabricated by a facile hydrothermal procedure in a mixture of ethanol and propylene glycol.When taken as anode materials in lithium ion batteries,the Fe_(3)O_(4)/CNTs nanocomposite has demonstrated excellent cycle performance with a specific capacity of 605 mAh g^(-1)ven after 300 cycles at the current density of 100 mA g^(-1).The addition of acid-treated CNTs can decrease the size of Fe_(3)O_(4) nanoparticles in the nanocomposite immensely due to the high specific surface area.The excellent electrochemical performances of the Fe_(3)O_(4)/CNTs nanocomposite were attributed to the microstructure characteristics as well as the remarkable electrical properties of CNTs and high capacity of the downsized Fe_(3)O_(4) nanoparticles.