The nanocomposites of carobn nanotube with Sb and SnSb_(0.5) as Li-ion battery anodes

摘要

Nanocomposites of carbon nanotubes (CNTs) with Sb and SnSb_(0.5) particles were prepared by chemical reduction of SnCl_2 and SbCl_3 precursors in the presence of CNTs.SEM and TEM imaging showed that the Sb and SnSb_(0.5) particles are uniformly deposited on the CNT exterior and in the CNT web. These CNT-metal composites are active anode materials for lithium ion batteries,showing improved cyclability compared to unsupported Sb and Sn-Sb particles and higher reversibled specific capacities than CNTs. The reversible capacities were as high as 462 mAh/g for CT-36wt.% Sb and 518 mAh/g for CNT-56 wt.% SnSb_(0.5) could only retain 17.7 and 23.5%,respectively of their initial capacitis in the same number of cycles. The improvement in cyclability may be attributed to the naoscale dimension of the metla particles and CNTs' role as a buffer in relieving the mechanical stress induced by specific volume changes in electrochemical lithium insertion and exraction reactions.