A Simple Synthesis of Nanocrystalline Binary Metal Chalcogenides in Alkaline Aqueous Solution

Nanocrystalline binary metal chalcogenides have been successfully synthesized through reactions between an alkaline aqueous solution with dissolved elemental S, Se, or Te and an aqueous solution of metal complex at low temperature under atmospheric pressure. The products were characterized by XRD, XPS, TEM, and optical property measurements. Elemental S, Se, and Te dissolved in the alkaline aqueous solution can rapidly make most metal chalcogenides crystallize well. Using metal complex instead of metal ion effectively avoids the occurrence of byproducts such as metal hydroxide or oxide in the alkaline aqueous solution. TEM micrographs show a variety of particle morphologies. The chalcogen sources and solvents are relatively simple and safe. The mechanism of formation of binary metal chalcogenides in the alkaline aqueous solutions is also discussed.