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研究了基于铜基底的TiO2纳米管阵列直接作为锂离子电池电极的储锂性能。以铜基底上生长的Cu(OH)2纳米棒阵列为模板,采用自牺牲模板法,通过外向包覆与内向刻蚀,制备了非晶态的TiO2纳米管阵列,然后将其在500℃下退火处理4 h,获得锐钛矿型TiO2纳米管阵列。采用X射线衍射、场发射扫描电镜、透射电镜、热重分析对样品进行表征;采用恒电流充放电、循环伏安和交流阻抗谱测试对退火前后TiO2纳米管阵列的电化学性能进行研究。结果表明:与非晶态的TiO2纳米管阵列相比,锐钛矿型TiO2纳米管阵列吸附水的含量低,结晶度高,电荷迁移阻力小,锂离子扩散系数大,结构稳定,具有更好的循环性能和倍率性能;在0.2C下,其首次放电比容量为353 mAh·g-1,经过40次循环后的放电比容量仍为243 mAh·g-1,在8C下的放电比容量为90 mAh·g-1。
The lithium-based properties of copper substrate-based TiO2 nanotube arrays as lithium-ion battery electrodes were studied. An array of Cu (OH) 2 nanorods grown on a copper substrate was used as a template to fabricate an amorphous TiO2 nanotube array by extrinsic cladding and inward etching using a self-sacrificial template method. Then, Annealed for 4 h to obtain an anatase TiO2 nanotube array. The samples were characterized by X-ray diffraction, field emission scanning electron microscopy, transmission electron microscopy and thermogravimetric analysis. The electrochemical properties of TiO2 nanotube arrays before and after annealing were investigated by galvanostatic charge-discharge, cyclic voltammetry and AC impedance spectroscopy. The results show that the anatase TiO2 nanotube arrays have lower water content, higher crystallinity, smaller charge transfer resistance, larger lithium ion diffusion coefficient, and better structure stability than the amorphous TiO2 nanotube arrays The specific discharge capacity at 35 ° C was 353 mAh · g-1 at 0.2 C, and the specific discharge capacity after 24 cycles was 243 mAh · g-1. The discharge capacity at 8 C 90 mAh · g-1.