Effect of synthesis conditions on MoS2 crystal structure

The relation between synthesis conditions of MoS2 (pressure, temperature) and its crystal structure have been studied. Crystal structure was analyzed using X-ray patterns. It was found that when MoS2 was obtained from the elements at a temperature less than 950 deg C and a pressure of some 40 atm and less, the structure of the compound was described by the absolutely disordered packing of S-Mo-S layers. The increase in synthesis temperature and pressure results in the precipitation of the rombohedral three-layer packing motif; on the whole, the structure remains heavily disordered. Annealing of specimens leads to the removal of defects which are not related to layer packing without any changes in disorder. At 47 Kb and 1000 deg C a three-layer rombohedral MoS2 modification has been formed