RESTACKING EXFOLIATED LAYERED COMPOUNDS

Single-molecular-layer MoS2, prepared by exfoliation of lithium-interc alated MoS2 in water or alcohols, was deposited on supports such as ca rbon black and alumina. X-ray diffraction patterns show that the stack ing of MoS2 layers can be perfectly turbostratic. The restacked MoS2 m ay or may not have water-bilayers between them, depending on the depos ition conditions. A special form of the Debye fomula for a turbostrati cally stacked layer system is introduced and calculated diffraction pa tterns are compared with the experimental results. On heating, the tur bostratic stacking converts to an ordered stacking, accompanied by a s tructural transformation of the MoS2 layers from a distorted octahedra l coordination to a trigonal-prismatic coordination along with dramati c changes in the optical and electrical properties.