小尺寸锂硅团簇SinLi （n=1-10）的理论研究  

Theoretical Studies on the Small Sized Lithium-silicon Clusters Si_nLi(n=1 10)

作　　者：王志强[1] 雷雪玲[1] 吴木生[1] 刘刚[1] 徐波[1] 欧阳楚英[1] 

机构地区：[1]江西师范大学物理与通信电子学院,南昌330022

出　　处：《无机材料学报》2013年第11期1237-1242,共6页Journal of Inorganic Materials

基　　金：国家自然科学基金(11264014;11064004;10964012);江西省自然科学基金(2010GZW0028)~~

摘　　要：采用密度泛函理论研究了锂硅团簇SinLi （n=1-10）的结构、稳定性和电子性质。计算结果表明锂原子处于硅团簇表面并且位于硅原子的桥位更稳定。SinLi团簇结合能表明锂原子的嵌入提高了硅团簇的稳定性。另外, 锂原子的结合能说明锂与硅团簇的相互作用随着硅团簇尺寸的减小而增强, 由此得到锂离子电池硅基负极材料嵌锂过程粉末化的一个重要原因。锂硅团簇的电离势、电子亲和势、化学势与能隙均表明Si4Li与Si7Li更容易失去一个α电子形成阳离子团簇。Theoretical studies on the structures, stabilities and electronic properties of SinLi （n=1-10） clusters were carried out by the density functional theory （DFT）. The results show that lithium atom prefers to stay at the surface of cluster and likes to be adsorbed on the bridge site. The binding energies indicate that the stabilities of SinLi clusters can be enhanced by adsorption of lithium atom. Additionally, lithium atom binding energies show that the interaction between lithium atom and silicon cluster increases as decreasing the cluster size, which is an important factor for the amorphization process upon lithiation of the silicon based anode materials for Li-ion batteries. The ionization potential, electron affinity potential, chemical potential and energy gap of the SinLi clusters all indicate that Si4Li and Si7Li are easier to lose α electron to form cationic clusters.

关 键 词：硅基负极材料 锂硅团簇 基态结构 电子性质 

分 类 号：O469[理学—凝聚态物理]