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Updated: Jun 25, 2025
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Integrating a Triplet-triplet Annihilation Up-conversion System to Enhance Dye-sensitized Solar Cell Response to Sub-bandgap Light
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Lanthanide-Sensitized Upconversion Iridium Complex via Triplet Energy Transfer
Kui Xu1, Lifeng Zheng2, Song-Song Bao1
1State Key Laboratory of Coordination Chemistry, School of Chemistry and Chemical Engineering, Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing, 210023, China.
Small Methods
|May 28, 2024
Summary
Researchers developed a new method to achieve upconversion luminescence in iridium (Ir) complexes using lanthanide-doped upconversion nanoparticles (UCNPs). This strategy enables Ir complexes to emit light under near-infrared excitation, overcoming previous limitations.
Area of Science:
- Materials Science
- Photochemistry
- Nanotechnology
Background:
- Cyclometalated iridium (Ir) complexes possess tunable optical properties valuable for biology and photocatalysis.
- Achieving upconversion luminescence in Ir complexes under near-infrared (NIR) light excitation remains a significant challenge.
Purpose of the Study:
- To develop a novel strategy for sensitizing upconversion luminescence in Ir complexes using lanthanide-doped upconversion nanoparticles (UCNPs).
- To investigate the mechanism of triplet energy transfer for enhanced luminescence.
Main Methods:
- Fabrication of core-shell structured NaYbF4:Tb@NaTbF4 UCNPs.
- Synthesis of new iridium phosphonate complexes.
- Utilizing Tb3+-mediated energy migration within UCNPs to sensitize Ir complex luminescence upon 980 nm excitation.
- Experimental and theoretical investigations of energy transfer pathways.
Main Results:
- Demonstrated successful sensitization of upconversion luminescence in Ir complexes via UCNPs.
- Identified triplet energy transfer from excited Tb3+ ions to the Ir complex triplet state as the key sensitization mechanism.
- Confirmed energy migration to the nanoparticle surface for efficient sensitization.
Conclusions:
- The developed hybrid UCNP-Ir complex system effectively achieves upconversion luminescence under NIR excitation.
- Triplet energy transfer is crucial for sensitizing Ir complex luminescence in this hybrid system.
- This work offers new possibilities for advanced hybrid Ir materials and UCNP-based nanomaterials.
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