碳纳米管修饰NaTi_(2)(PO_(4))_(3)电极材料的制备及应用

Preparation of Carbon Nanotube Decorated NaTi_(2)(PO_(4))_(3) Anode and Its Application in Sodium-ion Batteries

本文采用溶胶-凝胶法制备复合材料,通过加入碳纳米管来改善其电导率。SEM和TEM分析表明,结晶良好的NaTi_(2)(PO_(4))_(3)@C颗粒均匀地分散并嵌入碳纳米管中,复合材料由于碳层和碳纳米管构成的导电网络可以极大地促进电子/离子的传输。因此,所制备的电极在0.2C下可逆容量高达128.1 mAh·g^(-1),在10C下可逆容量高达94.3 mAh·g^(-1),循环性能优良,在2C下循环200次后容量保持率可达94.2%。从实验结果可以看出该材料应用前景广泛。

In this work, the carbon layer and carbon nanotube have been adopted to improve the low electronic conductivity of NaTi_(2)(PO_(4))_(3) anode for electrochemical sodium-ion storage. This designed composite is successfully prepared using a facile sol-gel route followed by the solid-state reaction. The SEM and TEM images reveal thatthe well crystallized NaTi_(2)(PO_(4))_(3)@C particles are uniformly dispersed and embedded in the CNT. In this composite, the formed conducting networks constructed by carbon layer and CNT can greatly facilitate the transport of electron/ion. Therefore, the as-prepared anode shows high reversible capacity of 128.1 mAh·g^(-1) at 0.2 C, good rate capability of 94.3 mAh·g^(-1) at 10 C and excellent cycling property with high capacity retention of 94.2 % after 200 cycles at 2 C.These results prove that the carbon layer and CNT co-decorated NaTi_(2)(PO_(4))_(3) composite is a promising anode material for rechargeable sodium-ion batteries.