Kinetic Study of the Intercalation of Cobaltocene by Layered Metal Dichalcogenides with Time-Resolved in Situ X-ray Powder Diffraction

Energy-dispersive X-ray diffraction (EDXRD) has been used to perform in situ kinetic studies on the intercalation of cobaltocene, Co(η-C 5 H 5 ) 2, into the layered dichalcogenides ZrS 2, 2H-SnS 2, 2H-SnSe 2, 2H-TaS 2, 2H-NbS 2, 1T-TaS 2, and TiS 2 . Integrated intensities of the Bragg reflections have been used to determine the extent of reaction (α) versus time for each of these reactions. The half-lives ( t 1/2 ) for reaction of an excess of cobaltocene with ZrS 2, 2H-SnS 2, 2H-SnSe 2, 2H-TaS 2, 2H-NbSe 2, and TiS 2 at 120 °C in dimethoxyethane were found to be <5, 31, 410, 16000, 2960, and >60000 s, respectively. A number of kinetic models have been considered, including the Avrami−Erofeyev ( m = 1.5) deceleratory nuclei-growth model and statistical simulation. The activation energy for the intercalation of Co(η-C 5 H 5 ) 2 in 2H-SnS 2 has been determined to be 41 kJ mol - 1 . The concentration and solvent dependence of the rate of Co(η-C 5 H 5 ) 2 intercalation into 2H-SnS 2 has also been determined. Surprisingly we find that the rate of intercalation is invariant to the initial Co(η-C 5 H 5 ) 2 concentration over the whole concentration range studied.