First principles study of the elastic properties of Li2MnSiO4ySy
First principles study of the elastic properties of Li2MnSiO4ySy
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Li2MnSiO4ySy弹性性能的第一性原理研究
DOI：
10.1039/c5ta00230c
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发表时间：
2015
影响因子：
11.9
通讯作者：
Dongsheng Xu
中科院分区：
文献类型：
--
作者：
Lin Zhu;Lin Li;Taimin Cheng;Dongsheng Xu
进行第一性原理计算以研究Li 2 MnSiO 4 ySy（y1/4 0，0.5，.1，2，4）的弹性性质，目的是改善硅酸盐材料在充电/放电循环期间的结构稳定性。计算结果表明，用硫代氧可使材料塑性得到全面改善。特别地，MnSiO 3 S和MnSiO 2 S 2的Pugh比B/G分别为1.97和2.79，显著大于区分韧性和脆性材料的临界值1.75。从这个意义上说，可以抑制脱锂过程中的韧-脆转变，并且在Li_2 MnSiO_4 ySy中实现每个分子式单元两个Li_2离子的可逆脱嵌。本研究为提高硅酸盐材料的电化学性能提供了一条新的途径。
First principles calculations were performed to investigate the elastic properties of Li2MnSiO4ySy (y ¼ 0, 0.5,.1, 2, 4) with the aim of improving the structural stability of silicate materials during charge/discharge cycles..Computational results show that the material ductility has been overall improved by sulfur substitution for.oxygen. In particular, the Pugh ratios B/G of MnSiO3S and MnSiO2S2 are 1.97 and 2.79, respectively,.significantly larger than the critical value 1.75 that separates ductile and brittle materials. In this sense, the.ductile–brittle transition during delithiation can be suppressed and the reversible deinsertion of two Li.ions per formula unit would be achieved in Li2MnSiO4ySy. This study provides an alternative way for.improving the electrochemical performance of silicate materials.