Laboratoire de Réactivité et Chimie des Solides (UMR CNRS 7314), Université de Picardie Jules Verne , 33 rue Saint Leu, 80039 Amiens Cedex, France.
Department of Chemistry, University of Bath , Bath BA2 7AY, United Kingdom.
ACS Appl Mater Interfaces. 2017 Mar 1;9(8):7050-7058. doi: 10.1021/acsami.6b14402. Epub 2017 Feb 13.
Lithium superionic conductor (LISICON)-related compositions LiSiXO (X = P, Al, or Ge) are important materials that have been identified as potential solid electrolytes for all solid state batteries. Here, we show that the room temperature lithium ion conductivity can be improved by several orders of magnitude through substitution on Si sites. We apply a combined computer simulation and experimental approach to a wide range of compositions (LiSiO, LiSiPO, LiSiAlO, LiAlSiPO, and LiAlSiGePO) which include new doped materials. Depending on the temperature, three different Li ion diffusion mechanisms are observed. The polyanion mixing introduced by substitution lowers the temperature at which the transition to a superionic state with high Li ion conductivity occurs. These insights help to rationalize the mechanism of the lithium ion conductivity enhancement and provide strategies for designing materials with promising transport properties.
锂离子超导体（LISICON）相关组合物 LiSiXO（X = P、Al 或 Ge）是被确定为全固态电池潜在固体电解质的重要材料。在这里，我们表明通过 Si 位取代可以将室温锂离子电导率提高几个数量级。我们对广泛的组成（LiSiO、LiSiPO、LiSiAlO、LiAlSiPO 和 LiAlSiGePO）应用了组合计算机模拟和实验方法，其中包括新的掺杂材料。根据温度的不同，观察到三种不同的锂离子扩散机制。取代所引入的多阴离子混合降低了向具有高锂离子电导率的超离子态转变的温度。这些见解有助于合理化锂离子电导率增强的机制，并提供具有有前途的传输性能的材料设计策略。
