Highly Luminescent Copper Iodide Cluster Based Inks with Photoluminescence Quantum Efficiency Exceeding 98%

摘要

Highly luminescent inks axe desirable for various applications such as decorative coating, art painting, and anticounterfeiting, to name a few. However, present inks display low photoluminescent efficiency requiring a strong excitation light to make them glow. Here, we report a highly luminescent ink based on the copper-iodide/l-Propyl-l,4-diazabicyclo[2.2.2]octan-l-ium (Cu_4I_6(pr-ted)_2) hybrid cluster with a quantum efficiency exceeding 98%. Under the interaction between the Cu_4I_6(pr-ted)_2 hybrid cluster and polyvinylpyrrolidone (PVP), the highly luminescent Cu_4I_6(pr-ted)_2/PVP ink can be facilely prepared via the one-pot solution synthesis. The obtained ink exhibits strong green light emission that originates from the efficient phosphorescence of Cu_4I_6(pr-ted)_2 nanocrystals. Attractively, the ink displays high conversion efficiency for the ultraviolet light to bright green light emission due to its wide Stokes shift, implying great potential for anticounterfeiting and luminescent solar concentrator coating.