InSb的Li嵌入电压轮廓曲线从头计算

Ab initio calculation of the voltage profile curve of Li insertions in InSb

InSb是很有应用前途的Li离子电池非碳类负极材料 .使用基于密度泛函理论的第一原理赝势法 ,计算了InSb在Li嵌入时的 12 5种不同情况下的总能、形成能以及平衡体积等 ,进而参考电压轮廓实验曲线 ,筛选出了若干条理论上可能的反应路径 ,得到了Li嵌入时的电压轮廓曲线 .结果表明 ,从体InSb相到Li3Sb相之间没有中间经历五个相及五个相以上的反应路径 ;中间经历一个相的最可能反应过程为Li+In4 Sb4 →Li1 In4 Sb4 ,11Li +Li1 In4 Sb4 →Li1 2 Sb4+4In ;中间经历四个相的仅有一条反应路径 :Li +In4 Sb4 →Li1 In4 Sb4 ,2Li +Li1 In4 Sb4 →Li3In4 Sb4 ,4Li +Li3In4 Sb4 →Li7In3Sb4 +In ,3Li+Li7In3Sb4 →Li1 0 In2 Sb4 +In ,2Li+Li1 0 In2 Sb4 →Li1 2 Sb4

InSb is an important non_carbon_bearing anode material for lithium (ion) batteries. An ab initio method with first_principles pseudopotentials based on the density functional theory has been used to calculate the total energies, formation energies and equilibrium volumes of Li intercalations in InSb in 125 possible cases. Comparing with the experimental voltage profile curve, we have picked out the possible reaction routes of Li insertions in InSb and a theoretical voltage profile curve is reached. Our results show that, from bulk InSb to bulk Li 3Sb, there are no possible reaction routes undergoing five or more intermediate phases. The most favored route for undergoing only one intermediate phase is Li+In 4Sb 4→Li 1In 4Sb 4, 11Li+Li 1In 4Sb 4→Li 12Sb 4+4In; whereas there exists only one reaction route for undergoing four intermediate phases, that is,Li+In 4Sb 4→Li 1In 4Sb 4,2Li+Li 1In 4Sb 4→Li 3In 4Sb 4,4Li+Li 3In 4Sb 4→Li 7In 3Sb 4+In,3Li+Li 7In 3Sb 4→Li 10In 2Sb 4+In,2Li+Li 10In 2Sb 4→Li 12Sb 4+2In.