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Updated: May 7, 2026

Integrating a Triplet-triplet Annihilation Up-conversion System to Enhance Dye-sensitized Solar Cell Response to Sub-bandgap Light
Published on: September 12, 2014
[C70] fullerene-sensitized triplet-triplet annihilation upconversion
Kyle Moor1, Jae-Hyuk Kim, Samuel Snow
1Department of Chemical and Environmental Engineering, School of Engineering and Applied Science, Yale University, New Haven, CT 06511, USA. jaehong.kim@yale.edu.
Abstract:
We herein report the first instance of using pristine C70 as a heavy-atom free organic sensitizer for efficient triplet-triplet annihilation upconversion (UC) for both green-to-blue and red-to-green UC using 9,10-bis(phenylethynyl)anthracene and perylene as acceptors, respectively. C70 achieved quantum yields of 8% and 0.8% for green-to-blue and red-to-green UC, 25 to 35 times higher than C60, and showed improved stability under continuous laser irradiation compared to the benchmark platinum(II)-octaethylporphyrin.
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