LnIII/CuI Bimetallic Nanoclusters with Enhanced NIR-II Luminescence

• DOI: 10.1021/jacs.4c09447
• Publication Date: 2024-10-14T14:41:13Z
• Authors: Tao Jia; Pei-Ming Cheng; Ming-Xuan Zhang; Wei-Dong Liu; Chong-Yang Li; Hai-Feng Su; La-Sheng Long; Lan-Sun Zheng; Xiang-Jian Kong

Coinage-metal clusters with excellent luminescence properties have attracted considerable interest due to their intriguing structures and potential applications. However, achieving strong near-infrared (NIR) luminescence in these clusters is highly challenging. Here, we have successfully synthesized the first LnIII/CuI bimetallic clusters, formulated as [LnCu54O6Cl3(2-MeO-PhC≡C)36] (ClO4)6 (Ln = Yb for YbCu54, Er for ErCu54, and Gd for GdCu54). Single crystal X-ray diffraction showed that the LnCu54 clusters have a three-layered core-shell structure, consisting of (LnO6)@Cu18Cl3@Cu36 units protected by 36 2-MeO-PhC≡C- ligands. Notably, the YbCu54 cluster exhibits significant NIR-II luminescence at 986 nm with the solid quantum efficiency of 33.3%, the highest among Cu clusters with NIR-II emission. This work not only reports the first category of LnIII/CuI clusters but also presents a method to enhance NIR luminescence in coinage-metal clusters through the incorporation of LnIII ions.