A novel room temperature method to nanocrystalline Ag2Se

Nanocrystalline Ag2Se was synthesized at room temperature through the reaction of AgNO3, Se, and KBH4 in pyridine. The products were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), and X-ray photoelectron spectroscopy (XPS). TEM revealed that the as-prepared Ag2Se grains were homogeneous and spherical, and their average size was about 25 nm. XPS analysis showed that the purity was good. Different solvent media were tested, and pyridine was found to be the most suitable one. The possible mechanism of the formation of Ag2Se grains is proposed. This novel mild method will be extended to prepare other nanocrystalline chalcogenides at room temperature.