Electrochemical and Structural Characterizations of InSb Nanoparticles Prepared Using a Sodium Naphthalenide Reduction Method

Abstract

InSb nanoparticles with a mean particle size of 10 nm prepared by the reduction of metal salts using sodium naphthalenide at 350 degrees C was discussed in terms of its electrochemical, ex situ X-ray diffraction (XRD) and transmission electron microscopy (TEM) characterizations. Ex situ XRD and TEM results revealed the progressive formation of extruded In from InSb, followed by the formation of Li3In2 and In3Li13 with a lithium alloy process. In addition, it was observed that Li2Sb and Li3Sb were formed as a result of the decomposition of InSb. During lithium dealloying, Li3Sb and In3Li13 were returned to Sb and In, respectively. Nanosized InSb particles showed a charge capacity of 590 mAh/g from the first-charge capacity of 670 mAh/g after 30 cycles, leading to a cycle retention ratio of 86%. This value was far superior to its bulk counterpart, which showed only a 48% capacity retention ratio after the same cycles. The improved capacity retention of the nanosized InSb was due to significantly decreased particle pulverization, compared to the bulk counterpart. (c) 2008 The Electrochemical Society.