Exploratory synthesis of new chalcogenide material by soft chemistry
I. Braems, M. T. Caldes, L. Cario, B. Corraze, C. Guillot-Deudon, E. Janod, S. Jobic.
Within the framework of this topic, we are interested in the reactivity of lamellar matrices containing oligomers (Qn)2- (Q = S, Se; n = 2-4) towards a metal.The reactivity of precursor La2O2S2 perfectly sums up our research theme.This compound, constructed from 2/∞[La2O2]2+ sheets separated by free pairs (S2)2-, can intercalate Cu at low temperature to lead to the compound La2O2Cu2S2.During this reaction, the sulfur pair (S2)2- is reduced by copper according to the reaction (S2)2- + 2 Cu° → 2 S2- + 2 Cu+. This reaction is reversible, the Cu atoms being able to be removed from La2O2Cu2S2 at 200 °C with I2 as oxidant.We have shown that similar reactions can be obtained using other polychalcogenides (BaS3, LaSe2...) or other transition elements (Fe, Co, Ni).We are currently exploring the reactivity towards alkali metals.
To go further : [Chalcogen Dimers], [Oligomers]