摘要
Tin (Sn) is one of the promising anode candidates for next generation applications in lithium ion batteries with high energy densities, but it suffers from drastic volume change (about 260%) upon lithiation. To address this issue, herein an efficient method is reported for coating Sn nanowires with an amorphous Al2O3 layer (Sn-Al2O3) based on a combination of mechanical pressure injection technique and partial dissolution of the anodic aluminum oxide template. Further, the Sn nanowires coated with Al2O3 are dispersed into carbon matrix (Sn-Al2O3-C) by ball milling. In this structure, Al2O3 helps to maintain structural integrity during charge-discharge process, and the introduced carbon matrix enhances electronic conductivity of the overall electrode. As a result, the Sn-Al2O3-C nanocomposite exhibits an enhanced cyclic and rate performance, namely, retaining the capacities of 1308.8 mAh g(-1) at the current density of 30 mA g(-1) after 20 cycles, 1063.3 mAh g(-1) at the current density of 200 mA g(-1), and 834.2 mAh g(-1) at the current density of 500 mA g(-1) after 100 cycles.