An electron microscopy study of intercalation in transition metal dichalcogenides

Abstract
Transmission electron microscopy and selected area electron diffraction have been used to study the structural changes produced in thin (0001) crystals of NbSe2 and MoS2 by intercalation with sodium in ammonia solution. Three distinct superlattice structures have been identified, one, with orthorhombic symmetry, associated with the presence of sodium, the other two, with hexagonal symmetry, associated with ammonia.