Rigsby Emily M, Miyashita Tsumugi, Jaimes Paulina, Fishman Dmitry A, Tang Ming Lee
Department of Chemistry, University of California, Riverside, Riverside, California 92521, USA.
Department of Bioengineering, University of California, Riverside, Riverside, California 92521, USA.
J Chem Phys. 2020 Sep 21;153(11):114702. doi: 10.1063/5.0017585.
In triplet-triplet annihilation based photon upconversion, controlling triplet energy transfer (TET) through the system is key to unlocking higher efficiencies. In this work, we vary the size of colloidally synthesized CdSe nanocrystals (NCs) to examine the effects on TET during photon upconversion, using steady-state measurements and transient absorption spectroscopy. As the CdSe NC size increases, the photon upconversion quantum yield (QY) decreases due to the decrease in the rate of TET from CdSe to the surface bound anthracene transmitter ligand, as expected for the Marcus description of energy transfer from the transmitter to the NC. Long microsecond transmitter lifetimes are critical to high photon upconversion QYs.
在基于三重态-三重态湮灭的光子上转换过程中，控制整个系统中的三重态能量转移（TET）是实现更高效率的关键。在这项工作中，我们通过改变胶体合成的CdSe纳米晶体（NCs）的尺寸，利用稳态测量和瞬态吸收光谱来研究光子上转换过程中对TET的影响。正如从发射体到纳米晶体的能量转移的马库斯描述所预期的那样，随着CdSe纳米晶体尺寸的增加，光子上转换量子产率（QY）由于从CdSe到表面结合的蒽发射体配体的TET速率降低而降低。长微秒级的发射体寿命对于高光子上转换量子产率至关重要。
