Intercalation of n-alkylamines into misfit layer sulfides

Abstract

Novel intercalation complexes of (PbS)_1.18( TiS₂)₂ and (PbS)_1.14(TaS₂)₂ two representative compounds of misfit layer sulfides, have been prepared by direct reaction with n-alkylamines (C_nH_{2n+ 1} NH₂)(n= 1–9). From the observed amine stoichiometry and lattice expansions, the most likely configuration for the intercalated amine molecules is one in which the latter are located at the van der Waals gap between two adjacent TS₂ slabs as a monolayer with the alkyl chain oriented parallel to the layers. Thermal deintercalation of the new phases occurred at temperatures below 250 °C and in the case of Ti intercalates, H₂S was released simultaneously with the amine deintercalation process. The intercalation process was confirmed to be reversible. Thus, the product obtained from the thermal treatment recovered the main features of the original host structure and, when mixed with the amine, yielded an intercalate of similar structural characteristics to those found using the original sulfide.