Gu Xiaofen, Chen Shuoran, Liang Zuoqin, Ju Xiaolei, Li Lin, Wang Xiaomei, Ye Changqing
Research Center for Green Printing Nanophotonic Materials, Suzhou Key Laboratory of New Energy Materials and Low Carbon Technologies, School of Materials Science and Engineering, Suzhou University of Science and Technology, Suzhou, 215009, China.
Phys Chem Chem Phys. 2023 Aug 23;25(33):22103-22110. doi: 10.1039/d3cp02199h.
Multi-wavelength hot-band excitation, forbidden in the conventional Stokes fluorescence mechanism, is found to be available with cascading triplet-triplet annihilation upconversion (TTA-UC). Selective excitation of Pt(II)octaethylporphyrin (PtOEP) by diode lasers with wavelengths of 532 nm, 589 nm, 635 nm, 655 nm, and 671 nm respectively can all induce 9,10-diphenylanthracene (DPA) to emit blue upconversion, with the maximum anti-Stokes shift of 0.95 eV in the microcrystals exposed to air. Whether the zero-vibrational energy level excitation or the hot-vibrational energy level excitation in the ground state, the PtOEP/DPA pair showed triplet-triplet energy transfer (TTET) efficiencies approaching ∼95%. The doped microcrystal samples without encapsulation can emit blue upconversion from green/yellow/red excitation with stability for ∼20 days under atmospheric conditions, demonstrating their potential applications in multiple information encryption.
在传统的斯托克斯荧光机制中被禁止的多波长热带激发，被发现可通过级联三重态 - 三重态湮灭上转换（TTA - UC）实现。分别用波长为532 nm、589 nm、635 nm、655 nm和671 nm的二极管激光器对八乙基卟啉铂（PtOEP）进行选择性激发，均可诱导9,10 - 二苯基蒽（DPA）发出蓝色上转换光，在暴露于空气中的微晶中最大反斯托克斯位移为0.95 eV。无论是基态的零振动能级激发还是热振动能级激发，PtOEP/DPA对都表现出接近95%的三重态 - 三重态能量转移（TTET）效率。未封装的掺杂微晶样品在大气条件下可从绿色/黄色/红色激发发出蓝色上转换光，且稳定性约为20天，展示了它们在多重信息加密中的潜在应用。
