Lithium intercalation mechanism for β-SnSb in Sn-Sb thin films

作     者：Qiang Ru Qin Tian She-jun Hu Ling-zhi Zhao 

作者机构：Laboratory of Quantum Information Technology School of Physics and Telecommunication Engineering South China Normal University Guangzhou 510006 China Department of Chemistry South China Normal University Guangzhou 510006 China 

出 版 物：《International Journal of Minerals,Metallurgy and Materials》 (矿物冶金与材料学报（英文版）)

年 卷 期：2011年第18卷第2期

页      面：216-222页

核心收录：

学科分类：081702[工学-化学工艺] 0709[理学-地质学] 0819[工学-矿业工程] 07[理学] 08[工学] 070203[理学-原子与分子物理] 0806[工学-冶金工程] 0817[工学-化学工程与技术] 0708[理学-地球物理学] 0805[工学-材料科学与工程（可授工学、理学学位）] 0703[理学-化学] 0802[工学-机械工程] 0801[工学-力学（可授工学、理学学位）] 0702[理学-物理学] 

基　　金：supported by the National Nature Science Foundation of China (No.50771046) the Educational Commission of Guangdong Province,China (No.C10179) 

主　　题：lithium batteries first-principles Sn-Sb alloys electronic structure thin films 

摘      要：Based on the first-principles plane wave pseudo-potential method, the electronic structure and electrochemical performance of LixSn4Sb4 （x=2, 4, 6, and 8） and LixSn12-xSb4 （x=9, 10, 11, and 12） phases were calculated. A Sn-Sb thin film on a Cu foil was also prepared by radio frequency magnetron sputtering. The surface morphology, composition, and lithium intercalation/extraction behavior of the fabricated film were characterized by scanning electron microscopy （SEM）, X-ray diffraction （XRD） and cyclic voltammetry （CV）. Lithium atoms can easily insert into and extract out of the β-SnSb cell due to the low lithium intercalation formation energy. It is found that lithium atoms first occupy the interstitial sites, and then Sn atoms at the lattice positions are replaced by excessive lithium. The dissociative Sn atoms continue to produce different Li-Sn phases, which will affect the electrode stability and lead to the undesirable effect due to their large volume expansion ratio. The calculated lithium intercalation potential is stable at about 0.7 V, which is consistent with the experimental result.