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Kinetics of photon upconversion by triplet-triplet annihilation: a comprehensive tutorial
Yoichi Murakami1, Kenji Kamada
1School of Engineering, Tokyo Institute of Technology, 2-12-1 Ookayama, Meguro-ku, Tokyo 152-8552, Japan. murakami.y.af@m.titech.ac.jp.
Physical Chemistry Chemical Physics : PCCP
|October 6, 2021
Summary
This tutorial explains photon upconversion (UC) via triplet-triplet annihilation (TTA), detailing kinetics crucial for developing new TTA-UC materials. Understanding TTA-UC processes and spin statistics is key to optimizing UC efficiency.
Area of Science:
- Photophysics and Photochemistry
- Materials Science
- Chemical Kinetics
Background:
- Photon upconversion (UC) via triplet-triplet annihilation (TTA) is a rapidly growing, multidisciplinary field.
- Understanding the complex photophysical processes and kinetics of TTA-UC is essential for material development and evaluation.
- Researchers from diverse backgrounds require a clear introduction to TTA-UC kinetics.
Purpose of the Study:
- To provide a comprehensive tutorial introduction to the kinetics of triplet-triplet annihilation photon upconversion (TTA-UC).
- To explain the fundamental concepts of TTA-UC, including spin statistics and their impact on UC efficiency.
- To derive steady-state and transient behaviors of TTA-UC and introduce data analysis tools.
Main Methods:
- Introduction of the standard TTA-UC model and its assumptions.
- Step-by-step analysis of spin statistics and their relation to the singlet branching ratio.
- Derivation of steady-state solutions and discussion of transient behaviors with equations.
Main Results:
- Explanation of the universal curve describing excitation intensity dependence of UC quantum yield.
- Introduction of functions for analyzing experimental steady-state and transient TTA-UC data.
- Provision of self-consistent derivations and relevant references for advanced understanding.
Conclusions:
- A solid grasp of TTA-UC kinetics is vital for advancing the field.
- The tutorial provides foundational knowledge and practical tools for researchers in TTA-UC.
- This work facilitates the development and evaluation of novel materials for photon upconversion.
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