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Updated: Oct 12, 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
Triplet-triplet annihilation upconversion with reversible emission-tunability induced by chemical-stimuli: a remote
Yaxiong Wei1, Haitao Xian, Xialei Lv
1Shenzhen Key Laboratory of Polymer Science and Technology, College of Materials Science and Engineering, Shenzhen University, Shenzhen 518060, China. xcao@szu.edu.cn clyang@szu.edu.cn.
Abstract:
Triplet-triplet annihilation upconversion (TTA-UC) has been widely studied, but a color-tunable TTA-UC system triggered by chemical stimuli has not yet been proposed. Herein, reversible acid/base switching of the TTA-UC emission wavelength is achieved for the first time by a simple platform, composed of a direct singlet-triplet (S0-T1) absorption photosensitizer, and proton-responsive 9,10-di(pyridin-4-yl)anthracene (DPyA) as an acceptor. The photosensitizer-acceptor pair exhibits efficient UC emission (quantum yield up to 3.3%, and anti-Stokes shift up to 0.92 eV) with remarkable contrast upon base/acid treatment (Δλem,max = 82 nm, 0.46 eV). In a proof-of-concept study, the color-adjustable TTA-UC emission was applied as a remote modulator to photo-control reversible chemical reactions for the first time. This platform enriches the portfolio of color-switchable TTA-UC, and the mechanism would inspire further development of smart UC systems and extend the application field of upconversion.
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