A Zero-Dimensional Hybrid Copper(I) Halide with Near-Unity PLQY for Highly Sensitive X-Ray Scintillation and...

The development of novel hybrid metal halides exhibiting near-unity photoluminescence quantum yield (PLQY) and responsiveness to visible light excitation are pivotal for X-ray imaging technologies and advancing solid-state lighting. Herein, we report a novel zero-dimensional hybrid copper(I) halide, (ATPP)₂Cu₂I₄ (ATPP = acetonyltriphenylphosphonium), and its structure features edge-sharing [Cu₂I₄]^{2 -} dimers. It displays bright broadband orange emission with a large Stokes shift of 304 nm and achieves a PLQY of 96.43%. The near-unity PLQY and weak self-absorption enable it exceptional X-ray scintillation performance with a light yield of 20 440 photons/MeV and a low detection limit of 47.06 nGy_air s^{- 1}. In addition, a warm white light-emitting diode (WLED) was obtained by integrating (ATPP)₂Cu₂I₄ as an orange phosphor onto a 365 nm UV LED chip, exhibiting a high color rendering index of 93 and a correlated color temperature of 3397 K. This work not only presents an outstanding candidate material for X-ray scintillator and warm WLED but also underscores the importance of low-dimensional hybrid copper(I) halides as versatile luminescent materials for multifunctional optoelectronic applications.