Triplet-triplet annihilation(TTA) upconversion-based materials have potential application in the broad range of research areas, including photocatalysis and life sciences. However, near-infrared(NIR)-to-blue upconvert...Triplet-triplet annihilation(TTA) upconversion-based materials have potential application in the broad range of research areas, including photocatalysis and life sciences. However, near-infrared(NIR)-to-blue upconverted emission is preferred for most of the practical applications, but developing a NIR-to-blue TTA upconversion system is a challenging task in photochemistry. In this work, a thermally activated delayed fluorescence(TADF) material with intense visible-to-NIR absorption is demonstrated that shows a longer triplet state lifetime(32 μs) and high triplet state energy(E_(T)= 1.55 e V). For the first time, a heavy atomfree NIR(λ_(ex)> 650 nm) to blue(λ_(em)< 460 nm) TTA upconversion system was devised, employing the dimeric borondifluoride curcuminoid TADF material as triplet photosensitizer(PS) and a large anti-Stokes shift(0.88 e V) along with moderate upconversion yield was achieved. Our work provides the solution and guidance for the future development of purely organic heavy atom-free NIR activating TTA upconversion system for a wide array of applications.展开更多
基金the National Natural Science Foundation of China (Nos. 21975053, 21975055, U2001222)Guangdong Basic and Applied Basic Research Foundation (Nos. 2019B1515120023, 2022B1515020041)Guangdong Province Universities and Colleges Pearl River Scholar Funded Scheme (2019) for financial support。
文摘Triplet-triplet annihilation(TTA) upconversion-based materials have potential application in the broad range of research areas, including photocatalysis and life sciences. However, near-infrared(NIR)-to-blue upconverted emission is preferred for most of the practical applications, but developing a NIR-to-blue TTA upconversion system is a challenging task in photochemistry. In this work, a thermally activated delayed fluorescence(TADF) material with intense visible-to-NIR absorption is demonstrated that shows a longer triplet state lifetime(32 μs) and high triplet state energy(E_(T)= 1.55 e V). For the first time, a heavy atomfree NIR(λ_(ex)> 650 nm) to blue(λ_(em)< 460 nm) TTA upconversion system was devised, employing the dimeric borondifluoride curcuminoid TADF material as triplet photosensitizer(PS) and a large anti-Stokes shift(0.88 e V) along with moderate upconversion yield was achieved. Our work provides the solution and guidance for the future development of purely organic heavy atom-free NIR activating TTA upconversion system for a wide array of applications.