Synthesis of Li(x)Na(2−x)Mn2S3 and LiNaMnS2 through redox-induced ion exchange reactions

Na2Mn2S3 was oxidatively deintercalated using iodine in acetonitrile to yield Na1.3Mn2S3, with lattice constants nearly identical to that of the reactant. Lithium was then reductively intercalated into the oxidized product to yield Li0.7Na1.3Mn2S3. When heated, this metastable compound decomposed to form a new crystalline compound, LiNaMnS2, along with MnS and residual Na2Mn2S3. Single crystal X-ray diffraction structural analysis of LiNaMnS2 revealed that this compound crystallizes in P-3m1 with cell parameters a=4.0479(6) Å, c=6.7759(14) Å, V=96.15(3) Å3 (Z=1, wR2=0.0367) in the NaLiCdS2 structure-type.

Structure of LiNaMnS2. Li and Mn are statistically distributed in edge-shared tetrahedral environments linked into infinite planes. Sodium ions occupy interlayer sites.Figure optionsDownload as PowerPoint slide