Nanocrystalline Binary, Ternary and Dilute Magnetic Semiconductors from Polychalcogenide Complexes

Abstract

ABSTRACTThe molecular polychalcogenide complexes [M(Se4)2]2−, (M=Mn, Zn, Cd, Hg), [Sn(Se4)3]2−, and [Cu4Se12]2− can be converted to the corresponding binary semiconducting solids. DMF and DMSO solutions of these complexes react with Se-abstracting reagents such as CN− and (n-Bu)3P to yield the corresponding binary solids at 155 °C or less. Appropriate stoichiometric mixtures of [Cu4Se12]2− and [In3Se15]3− react to give CulnSe2. Appropriate stoichiometric mixtures of [Cd(Se4)2]2− and [Mn(Se4)2]2− give solid solutions Cd1−xMnxSe where O<x<l. The Cd1−xMnxSe solid solutions were characterized by variable temperature magnetic measurements. Depending on the reaction conditions, metal precursor complex and Se-abstracting reagent used, the semiconductor particle size ranges from the quantum-size to the bulk regime. This method of synthesis produces the little known γ-MnSe in pure form.