Lantern-like Cu8 cluster for high-efficiency electrically driven light-emitting diodes
Yan-Yan Lin1, Jian Luo2, Bo-Wen Dai2
1MOE Key Laboratory for Analytical Science of Food Safety and Biology, Fujian Provincial Key Laboratory of Analysis and Detection Technology for Food Safety, Fujian Provincial Key Laboratory of Advanced Inorganic Oxygenated Materials, College of Chemistry, Fuzhou University, Fuzhou 350108, China. zhenlei@fzu.edu.cn.
Abstract:
A novel lantern-like Cu(I) cluster [Cu8(2-pyCC)6(N-triphosPh)2](PF6)2 (Cu8) was synthesized with high yield via ligand engineering, featuring mixed multidentate ligands of tris(diphenylphosphinomethyl)amine (N-triphosPh) and 2-pyridylethynyl (2-pyCCH). Its structure was thoroughly characterized using spectroscopic methods and X-ray crystallography. These techniques indicate that strategically introducing two kinds of multidentate ligands helps to enhance the overall stability of the lantern-like Cu8. Cu8 exhibits intense red photoluminescence (PL) at room temperature in the crystalline state, with a high PLQY of up to 31.4%. Significantly, Cu8 shows remarkable aggregation-induced emission enhancement (AIEE) in DMSO/H2O solution, as well as distinct temperature-responsive luminescence. Based on its excellent photophysical and chemical properties, Cu8 was employed as a light-emitting dopant in electrically driven organic light-emitting diodes (OLEDs) with an external quantum efficiency (EQE) of 14.3% at 500 cd m-2.
