C-Dot-Embedded SiO₂ Concentric Microspheres for Bright Fluorescent Photonic Pigments

Area of Science:

• Materials Science
• Nanotechnology
• Photonics

Background:

• Amorphous assembly of colloidal spheres creates structural color in photonic glasses (PGs).
• Functionalizing colloidal spheres enhances PG multifunctionality.
• Carbon dots (CDs) offer fluorescence properties.

Purpose of the Study:

• To develop a facile strategy for preparing SiO2 colloidal spheres with embedded carbon dots.
• To investigate the structural color and fluorescence properties of the resulting photonic glasses.
• To explore the potential applications of these novel photonic pigments.

Main Methods:

• Simultaneous preparation and silane-functionalization of carbon dots.
• Incorporation of functionalized CDs into SiO2 spheres via the Stöber reaction.
• Assembly of SiO2/CD spheres into photonic glasses and manipulation with carbon black.

Main Results:

• Formation of SiO2 spheres with a concentric SiO2/CD interlayer.
• Photonic glasses exhibiting structural color under visible light and fluorescence under UV light.
• Tunable structural color saturation and fluorescence intensity by incorporating carbon black.

Conclusions:

• A facile method for creating multifunctional SiO2/CD spheres was established.
• The resulting photonic glasses demonstrate combined structural color and fluorescence.
• These materials show promise for applications in sensing, imaging, LEDs, and anticounterfeiting.