Facile synthesis of efficient blue-light-emitting copper(I) halide hybrid phosphors for applications in pc-WLEDs and X-ray imaging

Organic-inorganic hybrid copper(I) halide semiconductors have attracted extensive attention for applications in phosphor-converted white light-emitting diodes (pc-WLEDs), X-ray imaging, and photodetectors because of their superior photo/radioluminescence, structural diversity, and eco-friendliness. In our previous work, we proposed a novel strategy for synthesizing highly efficient blue-emitting copper(I) halide hybrids by combining coordinated anionic inorganic modules with cationic derivatives. However, the complexity of the synthesis process has limited the practical application of this approach. To address this challenge, we report a facile, efficient, and rapid solution-based ultrasonic treatment method for synthesizing high-performance blue-emitting phosphors with this structural motif using inexpensive and commercially available tetraethylammonium halides (TEAX, X = Cl, Br, and I). The synergistic interplay of ionic and covalent bonds in these compounds endows them with a high photoluminescence quantum yield (PLQY) of 70% and excellent stability. These materials exhibit a thermally activated delayed fluorescence (TADF) mechanism, delivering outstanding performance in pc-WLEDs and X-ray imaging. Their exceptional properties highlight their significant potential for use in optoelectronic devices and X-ray scintillators. This work provides an important reference for the rapid synthesis of high-performance copper(I) halide hybrid phosphors and paves the way for their commercial application.