Thio sol-gel synthesis of titanium disulfide thin films and powders using titanium alkoxide precursors

Titanium alkoxides react at room temperature with H2S to form an amorphous titanium alkoxy-sulfide precursor which can be converted to TiS2 by heat-treatment in a flowing H2S gas stream. The reaction of titanium isopropoxide (Ti(OPri)4) with H2S in n-butylamine solvent has been studied using infrared spectroscopy (FTIR), gas chromatography/mass spectroscopy (GC/MS), XRD and EDAX measurements. Based on these studies, it is shown that a partially sulfidized alkoxide precursor forms through the partial replacement of some alkoxy groups by hydrosulfide moieties. The alkoxy-hydrosulfide is believed to form following a thiolysis-condensation mechanism similar to the hydrolysis-condensation process that occurs during the oxide sol-gel reaction. The alkoxy-hydrosulfide species then undergoes complete sulfidization at 800 °C in a stream of H2S to yield pure, hexagonal TiS2 in either film or powder forms.