School of Chemistry and Chemical Engineering, State Key Laboratory of Crystal Materials, Shandong University, Jinan 250100, People's Republic of China.
Hefei National Research Center for Physical Sciences at the Microscale, Department of Chemical Physics, University of Science and Technology of China, Hefei, Anhui 230026, China.
Sci Adv. 2023 Mar 29;9(13):eadg3587. doi: 10.1126/sciadv.adg3587.
Intrinsic dual-emission (DE) of gold nanoclusters in the near-infrared (NIR) are fascinating for fundamental importance and practical applications, but their synthesis remains a formidable challenge and sophisticated excited-state processes make elucidating DE mechanisms much more arduous. Here, we report an all-alkynyl-protected gold nanocluster, , showing a prolate Au tri-octahedral kernel surrounded by two Au(CZ-PrA) dimers, four Au(CZ-PrA) monomers, and two CZ-PrA bridges. exhibits distinguished photophysical properties including NIR DE at 820 and 940 nm, microsecond radiative relaxation, and 6.26% photoluminescent quantum yield at ambient environment in nondegassed solution. Combining systematic studies on steady/transient spectroscopy and theoretical calculation, we identified two triplet charge transfer (CT) states, ligand-to-kernel and kernel-based CT states as DE origins. Furthermore, this NIR DE exhibits highly independent and sensitive response to surrounding environments, which well coincide with its mechanism. This work not only provides a substantial structure model to understand a distinctive DE mechanism but also motivates the further development of NIR DE materials.
金纳米簇的本征双发射（DE）在近红外（NIR）中具有重要的基础意义和实际应用，但它们的合成仍然是一个巨大的挑战，复杂的激发态过程使得阐明 DE 机制更加困难。在这里，我们报告了一种全炔基保护的金纳米簇 ，它具有拉长的 Au 三八面体核，周围有两个 Au(CZ-PrA) 二聚体、四个 Au(CZ-PrA) 单体和两个 CZ-PrA 桥。 表现出独特的光物理性质，包括在非除气溶液中环境温度下在 820nm 和 940nm 处的近红外 DE、微秒辐射弛豫和 6.26%的光致发光量子产率。通过对稳态/瞬态光谱和理论计算的系统研究，我们确定了两个三重态电荷转移（CT）态，配体到核和基于核的 CT 态作为 DE 的起源。此外，这种近红外 DE 表现出对周围环境高度独立和敏感的响应，这与其机制很好地吻合。这项工作不仅提供了一个理解独特 DE 机制的重要结构模型，也激发了对近红外 DE 材料的进一步发展。
