Thermally induced microstructure and morphology transformations in molybdenum disulfide-octadecyltrimethylammonim layered nanocomposite

Microstructure of layered nanocomposite compound consisting of molybdenum disulfide single layers and the layers of octadecyltrimethylammonium molecules as well as the structure of destruction products of this hybrid compound were studied by high resolution transmission electron microscopy (HRTEM) and powder X-ray diffraction (XRD) techniques. Changes in composition, ordering and morphology of the host and guest layers of the compound occurring due to release of organic guest from the interlayer space of MoS2 on heating or on action of electronic beam have been revealed. Removal of the guest was found to initiate formation in the initial layered structure of the packets consisting of a few MoS2 layers which come close together within the distances of ca. 1-1.5 nm and 0.6-0.7 nm after heating at 250 °C and 400 °C, respectively. Leaving the guest also causes deformations of MoS2 layers resulting in their non-flat geometry. At 400 °C, strong bending of a part of the sulfide layers with the radius as small as 3-4 nm was observed.