Visible‐to‐ultraviolet (vis‐to‐UV) triplet‐triplet annihilation based photon upconversion (TTA‐UC) is achieved in a non‐volatile chromophoric ionic liquid (IL) for the first time. A novel IL is synthesized by combining UV‐emitting anion 4‐(2‐phenyloxazol‐5‐yl)benzenesulfonate (PPOS) and trihexyltetradecylphosphonium cation (P₆₆₆₁₄). The nanostructured organization of chromophoric anions is demonstrated by synchrotron X‐ray and optical measurements. When the IL is doped with a triplet sensitizer tris(2‐phenylpyridinato)iridium(III) (Ir(ppy)₃), the visible‐to‐UV TTA‐UC with a relatively low threshold excitation intensity of 61 mW cm⁻² is achieved. This is due to a large triplet diffusion coefficient in the IL (1.4×10⁻⁷ cm² s⁻¹) as well as a high absorption coefficient 15 cm⁻¹ and a long PPOS triplet lifetime of 1.55 ms, all implemented in the condensed IL system. This work demonstrates the unique potential of ILs to control chromophore arrangements for desired functions.

中文翻译：

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纳米结构发色离子液体中的可见光到紫外光子上转换。

首次在非挥发性发色离子液体（IL）中实现了基于可见光到紫外线（vis-to-UV）三重态-三重态湮灭的光子上转换（TTA-UC）。通过结合紫外发射阴离子 4-(2-苯基恶唑-5-基)苯磺酸盐 (PPOS) 和三己基十四烷基鏻阳离子 (P ₆₆₆₁₄ ) 合成了一种新型离子液体。同步加速器 X 射线和光学测量证明了发色阴离子的纳米结构组织。当IL掺杂三重态敏化剂三(2-苯基吡啶)铱(III) (Ir(ppy) _{3 )时，具有相对较低阈值激发强度61 mW cm} ^-2的可见光到紫外光TTA-UC为实现了。这是由于 IL 中的大三重态扩散系数 (1.4×10 ^-7  cm ²  s ^-1 ) 以及高吸收系数 15 cm ^-1和长 PPOS 三重态寿命 1.55 ms，所有这些都在凝聚态中实现。伊尔系统。这项工作展示了 IL 控制发色团排列以实现所需功能的独特潜力。