Related Experiment Video
Updated: May 1, 2026
06:08
Time-resolved Photophysical Characterization of Triplet-harvesting Organic Compounds at an Oxygen-free Environment Using an iCCD Camera
Published on: December 27, 2018
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Interplay between Host Structure, Oxygen Quenching, and Triplet-Triplet Annihilation Upconversion in Hybrid Polymer
Georgina H Burgoyne Morris1, Larissa Gomes Franca1, Abigail R Collins1
1Department of Materials Science & Metallurgy, University of Cambridge, 27 Charles Babbage Road, Cambridge CB3 0FS, U.K.
ACS Applied Optical Materials
|April 30, 2026
Summary
Oxygen quenching limits triplet-triplet annihilation upconversion (TTA-UC) efficiency. This study shows ureasil polymer structure impacts oxygen barrier properties, crucial for designing better TTA-UC materials for solar energy and sensing.
Area of Science:
- Materials Science
- Photochemistry
- Polymer Chemistry
Background:
- Triplet-triplet annihilation upconversion (TTA-UC) converts low-energy photons to higher energies, with applications in solar energy, sensing, and anticounterfeiting.
- Molecular oxygen significantly quenches excited triplet states, limiting TTA-UC efficiency under ambient conditions.
- Effective oxygen barrier properties in host materials are critical for robust TTA-UC performance.
Purpose of the Study:
- To investigate the oxygen barrier properties of ureasil polymers as host materials for ambient TTA-UC.
- To correlate ureasil structural characteristics (silica content, molecular weight, branching) with oxygen permeability.
- To elucidate the role of oxygen quenching and permeability in dictating TTA-UC efficiency.
Main Methods:
- Direct oxygen permeation measurements on ureasil polymers.
- Kinetic analysis of phosphorescence quenching of palladium-(II) octaethylporphyrin (PdOEP) to assess local oxygen levels.
- Correlation of structural parameters with measured oxygen barrier and TTA-UC performance.
Main Results:
- Ureasil structure significantly influences both bulk and local oxygen permeabilities.
- Variations in silica content, molecular weight, and polymer chain branching directly impact oxygen barrier effectiveness.
- Oxygen permeability was identified as the primary factor governing differences in ambient TTA-UC efficiency across various ureasil hosts.
Conclusions:
- Oxygen barrier properties are a critical design parameter for developing efficient ambient TTA-UC host materials.
- Tailoring ureasil polymer structure can optimize oxygen exclusion, thereby enhancing TTA-UC performance.
- This work provides a framework for designing advanced materials for TTA-UC applications by focusing on oxygen barrier characteristics.
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