Zinc-Doping Trap Engineering and FRET Synergy Enable Multicolor Room-Temperature Phosphorescence in Rice-Derived...

Area of Science:

• Materials Science
• Optoelectronics
• Nanotechnology

Background:

• Advanced information encryption requires multicolor room-temperature phosphorescence (RTP) materials with tunable afterglow.
• Existing materials often lack dynamic control over emission color and lifetime.

Purpose of the Study:

• To develop a synergistic strategy integrating trap engineering and Förster resonance energy transfer (FRET) for dynamic control of RTP emission.
• To create novel carbon dot@Zn-doping alumina (CDs@Zn_xAl₂O₃) composites with tunable multicolor RTP properties.

Main Methods:

• Fabrication of expired rice-derived carbon dots@Zn-doping alumina (CDs@Zn_xAl₂O₃) composites via an in situ preparation strategy.
• Engineering trap states within amorphous Al₂O₃ using in situ Zn²⁺ doping to modulate phosphorescence.
• Incorporating red-emissive TPA-β-CD-aggregates to establish efficient singlet-to-singlet and triplet-to-singlet FRET (SS-FRET/TS-FRET) pathways.

Main Results:

• The optimized CDs@Zn_1.5%Al₂O₃ composite exhibited an ultralong green RTP duration of up to 22 seconds.
• Tuning the Zn²⁺ doping ratio dynamically controlled the competition between FRET pathways, enabling finely adjustable multicolor RTP emissions.
• Demonstrated efficient SS-FRET and TS-FRET pathways with aggregation-induced emission (AIE) materials.

Conclusions:

• A versatile platform for creating color-tunable, ultralong RTP materials was established.
• The developed materials show direct applicability in time-gated, multilevel security encryption.
• Synergistic integration of trap engineering and FRET provides precise control over RTP characteristics.