Phosphorescent Carbon Dots as Long-Lived Donors To Develop an Energy Transfer-Based Sensing Platform

Area of Science:

• Materials Science
• Nanotechnology
• Analytical Chemistry

Background:

• Long-lived luminescent materials offer advantages for chemical sensing by eliminating real-time excitation and background fluorescence.
• Previous long-lived emitters in water had limitations like large size, high cost, and poor dispersibility.

Purpose of the Study:

• To create a stable, water-dispersible long-lived luminescent material for chemical sensing.
• To develop multicolor afterglow emissions and a sensitive mercury ion probe.

Main Methods:

• Covalent immobilization of phosphorescent carbon dots (CDs) within a silica matrix (CDs@SiO2).
• Fabrication of nonradiative energy transfer systems using CDs@SiO2 as donors and organic dyes as acceptors via surface micelle self-assembly.
• Design of a ratiometric phosphorescent probe for Hg2+ detection.

Main Results:

• Achieved stable afterglow emission (∼1.6 s lifetime) in aqueous dispersion using CDs@SiO2.
• Demonstrated efficient nonradiative energy transfer for multicolor afterglow emissions.
• Developed a sensitive ratiometric probe for Hg2+ detection based on triggered energy transfer.

Conclusions:

• CDs@SiO2 provides a versatile platform for aqueous long-lived luminescence applications.
• The developed system enables low-background, easily recognizable signals for chemical sensing.
• This approach opens opportunities for novel chemical sensors with enhanced performance.