Ambient facile synthesis of gram-scale copper selenide nanostructures from commercial copper and selenium powder

Grams of copper selenides (Cu2-xSe) were prepared from commercial copper and selenium powders in the presence of thiol ligands by a one-pot reaction at room temperature. The resultant copper selenides are a mixture of nanoparticles and their assembled nanosheets, and the thickness of nanosheets assembled is strongly dependent on the ratio of thiol ligand to selenium powder. The resultant Cu2-xSe (0 ≤ x ≤ 0.25) nanostructures were treated with hydrazine solution to remove the surface ligands and then explored as a potential thermoelectric candidate in comparison with commercial copper selenide powders. The research provides a novel ambient approach for preparation of Cu2-xSe nanocrystallines on a large scale for various applications.