title: A new ultrafast superionic Li-conductor: ion dynamics in Li11Si2PS12 and comparison with other tetragonal LGPS-type electrolytes.
abstract: We report on a new ultrafast solid electrolyte of the composition Li11Si2PS12, which exhibits a higher room-temperature Li ion diffusivity than the present record holder Li10GeP2S12. We discuss the high-pressure synthesis and ion dynamics of tetragonal Li11Si2PS12, and comparison is made with our investigations of related members of the LMePS family, i.e. electrolytes of the general formula Li11-xMe2-xP1+xS12 with Me = Ge, Sn : Li10GeP2S12, Li7GePS8, Li10SnP2S12. The structure and dynamics were studied with multiple complementary techniques and the macroscopic diffusion could be traced back to fast Li ion hopping in the crystalline lattice. A clear correlation between the diffusivity and the unit cell volume of the LGPS-type electrolytes was observed.
authors.affiliation: Max Planck Institute for Solid State Research, Heisenbergstr. 1, 70569 Stuttgart, Germany. a.kuhn@fkf.mpg.de b.lotsch@fkf.mpg.de.
authors.forename: Alexander
authors.initials: A
authors.lastname: Kuhn
authors.forename: Oliver
authors.initials: O
authors.lastname: Gerbig
authors.forename: Changbao
authors.initials: C
authors.lastname: Zhu
authors.forename: Frank
authors.initials: F
authors.lastname: Falkenberg
authors.forename: Joachim
authors.initials: J
authors.lastname: Maier
authors.forename: Bettina V
authors.initials: BV
authors.lastname: Lotsch