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03:02Colors and Magnetism
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02:52Stereoisomerism
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Isomerism in Complexes
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Dinuclear Heteroleptic Erbium Complexes for Improving Molecular-Based Light Upconversion in Solution?
Inès Taarit1, Quentin Sommer1, Laure Guénée2
1Department of Inorganic and Analytical Chemistry, University of Geneva, 30 Quai E. Ansermet, CH-1211 Geneva 4, Switzerland.
Inorganic Chemistry
|February 21, 2025
Summary
Researchers synthesized dinuclear erbium complexes using a novel ligand to enhance excited-state absorption (ESA) for light upconversion. The dinuclear erbium complex showed significant upconversion but no beneficial cross-relaxation effect was observed.
Area of Science:
- Coordination Chemistry
- Materials Science
- Photophysics
Background:
- Molecular-based excited-state absorption (ESA) is crucial for light upconversion technologies.
- Cross-relaxation (CR) is a potential mechanism to enhance ESA efficiency.
- Lanthanide complexes are promising candidates for luminescent materials.
Purpose of the Study:
- To synthesize and characterize dinuclear lanthanide complexes for boosted ESA via CR.
- To investigate the structural, thermodynamic, and photophysical properties of the synthesized adducts.
- To evaluate the upconversion performance of dinuclear erbium complexes.
Main Methods:
- Synthesis of a ditridentate polyaromatic ligand (L4) and its reaction with lanthanide cargoes [Ln(hfac)3].
- Crystal structure determination of dinuclear adducts [L4Ln2(hfac)6].
- Thermodynamic studies in dichloromethane and near-infrared (NIR) excited-state absorption (ESA) upconversion measurements.
Main Results:
- Formation of dimeric molecular scaffolds with dinuclear erbium complexes [L4Er2(hfac)6].
- Dinuclear erbium complex exhibits ESA light upconversion with blueish-green emissions.
- Upconversion quantum yield and brightness of the dinuclear adduct significantly surpass mononuclear intermediates but are comparable to related monomeric adducts.
Conclusions:
- The synthesized dinuclear erbium complexes demonstrate efficient light upconversion.
- No unambiguous beneficial cross-relaxation (CR) effect was observed in the dinuclear complexes.
- The study provides insights into the structure-property relationships of lanthanide-based upconversion materials.