Zuo Renjie, Ye Zecong, Liang Hui, Huo Yanping, Ji Shaomin
School of Chemical Engineering and Light Industry, Guangdong University of Technology, Guangzhou, 510006, China.
Guangdong Provincial Laboratory of Chemistry and Fine Chemical Engineering Jieyang Center, Jieyang, 515200, China.
Photochem Photobiol Sci. 2024 Jul;23(7):1309-1321. doi: 10.1007/s43630-024-00596-5. Epub 2024 Jun 5.
Current research of triplet-triplet annihilation upconversion (TTA-UC) faces difficulty such as overuse of organic solvents and quenching of excited triplet sensitizers by molecular oxygen. Herein, we propose an efficient and facile preparation strategy of TTA-UC microemulsion to overcome these issues. With simple device and short preparation process, air-stable TTA-UC with a high upconversion efficiency of 16.52% was achieved in microemulsion coassembled from TritonX114, tetrahydrofuran and upconverting chromophores (platinum octaethyl-porphyrin and 9,10-diphenylanthracene). This is comparable to the highest UC efficiency ever reported for TTA-UC microemulsion systems. The excellent UC performance of TX114-THF could be attributed to two perspectives. Firstly, small-size micelle accommodated chromophores up to high concentrations in organic phase, which promoted efficient molecular collision. Additionally, high absorbance at 532 nm ensured full use of excitation light, getting more long wavelength photons involved in the TTA-UC process. Moreover, air-stable TTA-UC also performed well in microemulsion with various surfactants, including nonionic surfactants (Tween 20, Tween 80, Triton X-110, Triton X-114), ionic surfactants (sodium dodecyl sulfate, cetyltrimethyl ammonium bromide) and block copolymers (pluronic F127, pluronic P123), through three conjectural assembly models according to the structural characteristics of surfactant molecules (concentrated, uncompacted and scattered). These discoveries could provide estimable reference for selection of surfactants in relevant fields of TTA-UC.
目前，三重态-三重态湮灭上转换（TTA-UC）研究面临有机溶剂过度使用以及激发三重态敏化剂被分子氧猝灭等难题。在此，我们提出一种高效简便的TTA-UC微乳液制备策略来克服这些问题。借助简单的装置和简短的制备过程，在由TritonX114、四氢呋喃和上转换发色团（八乙基铂卟啉和9,10-二苯基蒽）共组装而成的微乳液中，实现了具有16.52%的高上转换效率且对空气稳定的TTA-UC。这与TTA-UC微乳液体系所报道的最高上转换效率相当。TX114-THF优异的上转换性能可从两个方面来解释。首先，小尺寸胶束能够在有机相中容纳高浓度的发色团，从而促进了高效的分子碰撞。此外，在532nm处的高吸光度确保了激发光的充分利用，使得更多长波长光子参与到TTA-UC过程中。而且，通过根据表面活性剂分子结构特征（浓缩型、松散型和分散型）提出的三种推测性组装模型，对空气稳定的TTA-UC在含有各种表面活性剂的微乳液中也表现良好，这些表面活性剂包括非离子表面活性剂（吐温20、吐温80、Triton X-110、Triton X-114）、离子表面活性剂（十二烷基硫酸钠、十六烷基三甲基溴化铵）和嵌段共聚物（普朗尼克F127、普朗尼克P123）。这些发现可为TTA-UC相关领域中表面活性剂的选择提供有价值的参考。
