The thio-sol-gel synthesis of titanium disulfide and niobium disulfide Part 1. - Materials chemistry

Investigations pertaining to the synthesis of titanium disulfide (TiS2) have so far been focused on solid state reactions, low temperature chemical techniques and vapor phase reactions using titanium tetrachloride (TiCl4) as the starting material. In: this paper, we have investigated the potential of titanium tetraalkoxides [Ti (OR)(4)], which have been widely used for the synthesis of oxides by the sol-gel approach, for the synthesis of TiS2 via the thio-sol-gel process. The mechanism of the reaction of titanium isopropoxide {Ti(OPri)(4)} with H2S in benzene has been studied using infrared spectroscopy (FTIR), gas chromatography (GC) and chemical analysis. Based on these studies, it has been determined that the precipitate obtained from the reaction forms following a thiolysis-condensation mechanism similar to the hydrolysis-condensation mechanism that operates in the oxide sol-gel process. The precipitate, which is an alkoxysulfide, can be converted to TiS2 by heat treatments in flowing H2S. The influence of modifying agents, the role of solvent's and the alkoxy group [in Ti(OR)(4)] on the formation of the alkoxysulfide precipitate have also been presented and discussed. Finally, the applicability of this process for the synthesis of NbS2 has also been demonstrated.