%0 Journal Article %A He, Liqing %A Li, Hai-Wen %A Nakajima, Hironori %A Tumanov, Nikolay %A Filinchuk, Yaroslav %A Hwang, Son-Jong %A Sharma, Manish %A Hagemann, Hans %A Akiba, Etsuo %T Synthesis of a Bimetallic Dodecaborate LiNaB12H12 with Outstanding Super Ionic Conductivity %J Chemistry of Materials %@ 0897-4756 %V 27 %N 16 %P 5483-5486 %D 2015 %U http://pubs.acs.org/doi/abs/10.1021/acs.chemmater.5b01568 %R 10.1021/acs.chemmater.5b01568 %U http://archive-ouverte.unige.ch/unige:75041 %X A bimetallic dodecaborate LiNaB12H12 has been successfully synthesized for the first time, through a sintering process of LiBH4, NaBH4 and B10H14. LiNaB12H12 has a cubic Pa-3 space group symmetry at room temperature, and transforms into a high temperature phase with Fm-3m symmetry at 488 K, which is lower than that of Li2B12H12 and Na2B12H12. The ionic conductivity at 550 K reaches 0.79 S/cm, which is approximately 8 times higher than that of Na2B12H12 and 11 times higher than that of Li2B12H12. The Li/Na compositional and thus an induced positional disorder in LiNaB12H12 are suggested to be responsible for the reduced phase transition temperature and the improved super ionic conductivity compared to its monometallic counterparts.