Aqueous synthesis of high bright Ag2SeZnSe quantum dots with tunable near-infrared emission

• Ag2SeZnSe nanocrystals are prepared directly in aqueous media at low temperature.
• Ag2SeZnSe nanocrystals show excellent water solubility and colloidal stability.
• Ag2Se nanocrystals exhibit tunable near-infrared emission with ultrasmall size.
• Ag2SeZnSe nanocrystals show high quantum yield with low cytotoxicity.
• Ag2SeZnSe nanocrystals are stable over a month at room temperature in the air.

Efficient aqueous synthetic methods for near-infrared quantum dots as bioimaging agents are urgently required. In this work, a simple and fast synthesis of highly luminescent, near-infrared Ag2Se quantum dots (QDs) in aqueous media is reported. The method avoids high temperature, pressure and organic solvents to directly generate water-dispersible Ag2Se QDs. The photoluminescence emission of Ag2Se QDs ranges from 835 to 940 nm by different Ag:Se molar ratio. Using the ZnSe as a shell, the quantum yield reaches up to 42%. The Ag2SeZnSe QDs with high quantum yield, near-infrared and low cytotoxic could be used as good cell labels, showing great potential applications in bio-imaging.

Figure optionsDownload as PowerPoint slide