Synthesis and characterization of 1,2,3,4 tetrahydroquinoline intercalated into MoS2 in search of cleaner fuels

Abstract

Two different morphologies of MoS2 (short and long sheets) were utilized to elucidate the intercalation mechanism of 1,2,3,4 tetrahydroquinoline (THQ). MoS2 (short sheets) and molybdenite (MB) (long sheets) were exfoliated and restacked in the presence of THQ. The x-ray diffraction patterns of both samples show a new reflection in the 001 plane, which implies a lowering of symmetry and corresponds to an expansion of the layers by approximately 12.3 Å. In the MoS2-THQ sample, 80% of the MoS2 was intercalated and 20% remained stacked. In the MB-THQ sample, 30% of MB was intercalated while 70% remained stacked. X-ray absorption structure (XAS) studies showed changes in atomic geometry and coordination. The x-ray absorption near-edge spectra showed shifts in the geometry of the intercalated MoS2 and MB sample compared to the unintercalated samples. Extended x-ray absorption fine structure studies showed lower coordination numbers compared to the untreated samples. Infrared spectroscopy characterization of these same samples suggests intercalation and partial dehydrogenation of the THQ.