Lithium reactivity with III–VI layered compounds

The reactivity of lithium with layered chalcogenides InSe and In₂Se₃ is studied using transmission electron microscopy (TEM), electrochemical potential spectroscopy (EPS) and Raman scattering (RS). It is found that for x(Li)≥0.1 in Li_xInSe, the host material decomposes with the formation of lithium selenide. The presence of Li₂Se is confirmed by Raman spectroscopy. The insertion of Li into In₂Se₃ appears more stable with the occurrence of a superlattice formation at x(Li)≈0.25. The superstructure corresponding to the 2a×2a lattice is consistent with the EPS measurements of Li_xIn₂Se₃.