Toyama Kazuki, Tanaka Yuya, Yoshizawa Michito
Laboratory for Chemistry and Life Science, Institute of Integrated Research, Institute of Science Tokyo 4259 Nagatsuta, Midori-ku Yokohama 226-8501 Japan
Chem Sci. 2025 Aug 4. doi: 10.1039/d5sc04122h.
Sulfur-bridged copper clusters are important biocomponents, yet their artificial analogues have rarely been studied due to poor solubility and stability. Here we report the preparation of red-to-near-infrared (NIR) phosphorescent solutions from multinuclear Cu S clusters upon encapsulation by aromatic micelles in water. For instance, whereas a 2-mercapto-6-methylpyridine-based CuS cluster shows no solution-state emission owing to its insolubility in common solvents, the encapsulated cluster emits strong red-to-NIR phosphorescence ( = 34%; = 550-850 nm) with high stability, even under aerobic and ambient conditions. Similar host-guest complexes are also obtained from analogous CuS clusters, displaying substituent-dependent red-to-NIR emission in water. The present method is applicable to larger CuS and smaller CuI clusters to generate aqueous, red, yellow, and green emissive solutions. Notably, the resultant host-guest solution can be used as aqueous colorless ink, for potential security applications, which exhibits strong emission when painted on paper in the red-to-NIR region upon UV-light irradiation.
硫桥联铜簇是重要的生物成分，然而由于其溶解性和稳定性较差，它们的人工类似物很少被研究。在此，我们报道了通过在水中用芳香族胶束包封多核Cu₂S簇来制备从红色到近红外（NIR）磷光溶液。例如，基于2-巯基-6-甲基吡啶的CuS簇由于在常见溶剂中不溶而在溶液状态下不发光，但包封后的簇即使在有氧和环境条件下也能发出强烈的从红色到近红外磷光（量子产率 = 34%；波长 = 550 - 850 nm），且具有高稳定性。类似的主客体配合物也可从类似的CuS簇获得，在水中呈现出依赖取代基的从红色到近红外发射。本方法适用于更大的CuS和更小的CuI簇，以生成水性的红色、黄色和绿色发光溶液。值得注意的是，所得的主客体溶液可用作水性无色墨水，用于潜在的安全应用，当在紫外光照射下涂覆在纸上时，在红色到近红外区域会发出强烈的光。
