Preparation and electrochemical performance of CNT/Fe 3 O 4 @C for lithium-ion battery

In order to solve the problem of poor conductivity and expansion of ferric oxide (Fe 3 O 4 ), firstly, the composite powder of carbon nanotubes (CNTs) and nanoFe 3 O 4 was prepared, then CNT/Fe 3 O 4 encapsulated by pitch (Fe 3 O 4 /CNT@pitch) powder were obtained by solution coating, and further carbonization to obtain CNT/Fe 3 O 4 @C nanocomposites. Our results indicate that CNT content in the CNT/Fe 3 O 4 @C has significant effect on the electrochemical performance. CNT/Fe 3 O 4 @C with high (5.88wt%) content of CNT (CNT-M/Fe 3 O 4 @C) has more excellent rate characteristics, which is due to its low charge transfer resistance and high conductivity, while CNT/Fe 3 O 4 @C with low (0.31wt%) content of CNT (CNT-S/Fe 3 O 4 @C) exhibits the highest reversible specific capacity of 588.8 mAh g −1 when compared with 425.6 mAh g −1 for CNT-M/Fe 3 O 4 @C after 300 cycles at 100 mA g −1 , which is due to its low specific surface area. The simple preparation process of CNT/Fe 3 O 4 @C is worth industrialization.