The thio-sol-gel synthesis of titanium disulfide and niobium disulfide. Part 2.–Morphology, defect structure and electrochemical characteristics of titanium disulfide

Abstract

The thio-sol-gel process has been used to synthesize TiS ₂ powders exhibiting different morphologies, from randomly agglomerated to radially oriented TiS ₂ crystallites from a single precursor. It has been shown that different heat-treatment conditions can be utilized to simultaneously control the morphology of the sulfide powder and its defect concentration. Thus a variety of morphologies with crystallite sizes in the range of 2 µm to less than 0.5 µm and with defect concentrations ( _x in Ti _1+x S ₂ ) in the range of 0.003≤x≤0.03 have been synthesized. The crystallite sizes have been quantified using scanning electron microscopy and defect concentrations have been measured by determining the lattice parameter of the crystal. The performance of these materials as cathodes in secondary lithium batteries has also been evaluated and correlated to the crystallite size distributions and defect concentration.