A zero-dimensional hybrid halide with superior water resistance for high-efficiency X-ray scintillation and solid-state lighting†

Abstract

In recent years, hybrid metal halides have gained considerable attention for optoelectronic applications due to their outstanding photophysical properties, despite challenges with stability. In this study, we present the design and synthesis of a highly stable and efficient zero-dimensional (0D) hybrid copper(I) halide, [FBZPA]₄Cu₅Br₁₃ (FBZPA = protonated 1-(4-fluorobenzyl)piperazine)), for advanced scintillation and solid-state lighting applications. This material exhibits efficient yellow light emission with a photoluminescence quantum yield of 88.5%, driven by radiative recombination of self-trapped excitons, which is facilitated by structural deformation and strong electron–phonon coupling within the 0D structure. [FBZPA]₄Cu₅Br₁₃ shows excellent scintillation properties, including a high light yield (∼39 100 photons MeV⁻¹), a low detection limit (0.102 μGy_air s⁻¹), and a high spatial resolution (15 lp mm⁻¹), making it an ideal candidate for high quality X-ray imaging. Additionally, we fabricated a white light-emitting diode (WLED) by combining [FBZPA]₄Cu₅Br₁₃ with a commercial blue phosphor on a UV chip. The WLED exhibited a high color rendering index of 90 with stable emission. It demonstrates remarkable stability, retaining its structure and optical properties after exposure to water, and intense light, without requiring encapsulation or chemical modifications. This study highlights [FBZPA]₄Cu₅Br₁₃ as a promising material for next-generation scintillation and solid-state lighting applications.