TY - JOUR
T1 - Absolute Method to Certify Quantum Yields of Photon Upconversion via Triplet-Triplet Annihilation
AU - Yanai, Nobuhiro
AU - Suzuki, Kengo
AU - Ogawa, Taku
AU - Sasaki, Yoichi
AU - Harada, Naoyuki
AU - Kimizuka, Nobuo
N1 - Funding Information:
This work was partly supported by JSPS KAKENHI grant numbers JP17H04799, JP16H06513, and The Yoshida Foundation for the Promotion of Learning and Education.
Publisher Copyright:
© 2019 American Chemical Society.
PY - 2019/11/21
Y1 - 2019/11/21
N2 - For the consistent development of the field of photon upconversion via triplet-triplet annihilation (TTA-UC), it is pivotal to know the true quantum yield of TTA-UC emission. Although TTA-UC quantum yields have been determined by common relative measurements using quantum yield standards, there is still a discrepancy between the reported values even for the benchmark sensitizer-emitter pair of platinum(II) octaethylporphyrin (PtOEP) and 9,10-diphenylanthracene (DPA). Here, to resolve this situation, we show a method to obtain the absolute quantum yield of TTA-UC photoluminescence. The difficulty in obtaining absolute TTA-UC quantum yield by the integrating sphere measurement is to accurately calibrate the contribution of reabsorbed upconverted emission by triplet sensitizers. The reabsorption correction is successfully carried out by comparing sensitizer phosphorescence with and without the integrating sphere. An absolute TTA-UC quantum yield of the PtOEP-DPA pair is obtained as 36%, which shows a good agreement with the relative TTA-UC quantum yield. An absolute TTA-UC quantum yield of another red-to-blue TTA-UC pair, platinum(II) meso-tetraphenyltetrabenzoporphyrin (PtTPBP) and 2,5,8,11-tetra-tert-butylperylene (TTBP), is obtained as 27%. These absolute TTA-UC quantum yields can be used as certified values to check the measurement setup and sample condition for determining relative TTA-UC quantum yields in each laboratory.
AB - For the consistent development of the field of photon upconversion via triplet-triplet annihilation (TTA-UC), it is pivotal to know the true quantum yield of TTA-UC emission. Although TTA-UC quantum yields have been determined by common relative measurements using quantum yield standards, there is still a discrepancy between the reported values even for the benchmark sensitizer-emitter pair of platinum(II) octaethylporphyrin (PtOEP) and 9,10-diphenylanthracene (DPA). Here, to resolve this situation, we show a method to obtain the absolute quantum yield of TTA-UC photoluminescence. The difficulty in obtaining absolute TTA-UC quantum yield by the integrating sphere measurement is to accurately calibrate the contribution of reabsorbed upconverted emission by triplet sensitizers. The reabsorption correction is successfully carried out by comparing sensitizer phosphorescence with and without the integrating sphere. An absolute TTA-UC quantum yield of the PtOEP-DPA pair is obtained as 36%, which shows a good agreement with the relative TTA-UC quantum yield. An absolute TTA-UC quantum yield of another red-to-blue TTA-UC pair, platinum(II) meso-tetraphenyltetrabenzoporphyrin (PtTPBP) and 2,5,8,11-tetra-tert-butylperylene (TTBP), is obtained as 27%. These absolute TTA-UC quantum yields can be used as certified values to check the measurement setup and sample condition for determining relative TTA-UC quantum yields in each laboratory.
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U2 - 10.1021/acs.jpca.9b08636
DO - 10.1021/acs.jpca.9b08636
M3 - Article
C2 - 31663744
AN - SCOPUS:85075010973
SN - 1089-5639
VL - 123
SP - 10197
EP - 10203
JO - Journal of Physical Chemistry A
JF - Journal of Physical Chemistry A
IS - 46
ER -