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Updated: Jun 20, 2025

Integrating a Triplet-triplet Annihilation Up-conversion System to Enhance Dye-sensitized Solar Cell Response to Sub-bandgap Light
Published on: September 12, 2014
Optimizing Upconversion Quantum Yield via Structural Tuning of Dipyrrolonaphthyridinedione Annihilators
Alexandra J Lyons1, Lukas Naimovičius1, Simon K Zhang1
1Department of Chemistry and Biochemistry, University of California San Diego, 92093, La Jolla, CA, USA.
Abstract:
Triplet-triplet annihilation upconversion (TTA-UC) is a photophysical process in which two low-energy photons are converted into one higher-energy photon. This type of upconversion requires two species: a sensitizer that absorbs low-energy light and transfers its energy to an annihilator, which emits higher-energy light after TTA. In spite of the multitude of applications of TTA-UC, few families of annihilators have been explored. In this work, we show dipyrrolonaphthyridinediones (DPNDs) can act as annihilators in TTA-UC. We found that structural changes to DPND dramatically increase its upconversion quantum yield (UCQY). Our optimized DPND annihilator demonstrates a high maximum internal UCQY of 9.4 %, outperforming the UCQY of commonly used near-infrared-to-visible annihilator rubrene by almost double.
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