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Integrating a Triplet-triplet Annihilation Up-conversion System to Enhance Dye-sensitized Solar Cell Response to Sub-bandgap Light
Published on: September 12, 2014
Interface-Confined Triplet Sensitization and Photon Upconversion in Pyrene-Tetracyanobenzene Charge-Transfer
Jianlei Han1, Zhiying Bai2, Jiao Mu2
1College of Biological and Chemical Engineering, Jiaxing University, Jiaxing 314001, China.
Abstract:
Micro-cocrystals of the intermolecular charge-transfer (CT) complex formed from pyrene and tetracyanobenzene can be fabricated via a solution-based method. Intersystem crossing of the directly excited CT exciton in the cocrystal is observed, yielding a CT triplet exciton that undergoes efficient triplet-triplet energy transfer to a diphenylanthracence (DPA)-based triplet acceptor. For the first time, we demonstrate that these micro-cocrystals can act as triplet sensitizers to upconvert the emission of liquid-state DPA triplet acceptors, enabling highly efficient triplet-triplet annihilation photon upconversion (TTA-UC) from 532 to 430 nm. This work demonstrates the utilization of CT excitons as triplet sensitizers in a TTA-UC process, providing a novel approach for efficient and heavy-atom-free UC systems.
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