Formation of Transition Metal Sulfides by the Decomposition of Their Dithiolato Complexes

Abstract

The thermal behavior of dithiolato complexes of Ni, Co, Fe, and Mo has been investigated. For this purpose simple monoalkyldithiocarbamate, dialkyldithiocarbamate, and xanthate complexes of the metals were used. Since the objective of this study was to ascertain if these complexes could be used to prepare racial sulfides directly, the inorganic residues left after the decomposition of the complexes have been extensively studied. Of the different techniques used (TGA, powder X-ray diffraction, GC/MS, and heated stage XRD), the last was found to be very powerful and the method of choice. With this method the successive decomposition of complexes and, consequently, the pathway for the formation of final sulfides could be established. In this work it was found that the metal, type of ligands, and atmospheric environment are all important parameters in the formation of sulfides upon thermolysis. This study suggests that by judicious selection of these parameters, many desired transition metal sulfides can be prepared by thermolysis of the metal complexes.