Growth of photoluminescent Ag2Se nanowires from a simple precursor solution

Abstract

Near-infrared (NIR) photoluminescent silver selenide (Ag₂Se) nanowires were synthesized from a precursor solution containing silver nitrate, elemental selenium and hydrazine hydrate (N₂H₄·H₂O). Elemental selenium was reduced by N₂H₄·H₂O and then reacted with silver nitrate. N₂H₄ also coordinated with the precursors and the resulting Ag₂Se nanowires. The single-crystalline Ag₂Se nanowires (tetragonal α-Ag₂Se) grown from the precursor solution had varying diameters depending on the reaction time. After storing at 60 °C for 24 h, Ag₂Se nanowires emitting in the NIR window were obtained. With increasing diameter, the emission intensity decreased until the nanowires became non-photoluminescent. The photoluminescence lifetime and photostability of the Ag₂Se nanowires were similar to those of Ag₂Se quantum dots reported previously. We expect that these Ag₂Se nanowires will hold a broad spectrum of applications in nanoscale optical or photoelectronic devices.