Environment-friendly and highly efficiency organic antimony halide scintillator for light emitting diode and X-ray imaging

Abstract

Metal halides with high luminescence properties have emerged as novel candidate scintillators for X-ray detection and imaging. Low-dimensional organic-inorganic halide, which consists of heavy metals with a free composition, provides unique optical properties and luminescence applications. Herein, a lead-free zero-dimensional antimony hybrid single crystal-(MPP)₂SbCl₅ (MPP = Methyltriphenylphosphonium) is developed through facile synthesis with nearly 100 % photoluminescence quantum yield peaking at 590 nm. The (MPP)₂SbCl₅ single crystal exhibits fantastic thermal stability with a phase transition temperature of 600 K and air stability with exposure to air for at least 6 months. Moreover, single crystals with a product yield of 100 % are prepared by an environment-friendly method that is devoid of any toxic solvents and pollution throughout the process. A light-emitting diode device using broad-band emissive single crystal (MPP)₂SbCl₅, green emission—MPP₂MnCl₄, and blue emission—anthracene on a 365 nm GaN chip exhibits a pure white light (color rendering index, CRI = 93). Meanwhile, (MPP)₂SbCl₅ single crystal exhibits excellent scintillation performance, with a high light yield of 28,000 photons MeV⁻¹ and a low detection limit of 532 nGy s⁻¹. The flexible scintillation screen based on (MPP)₂SbCl₅ was fabricated using the vacuum filtration method, displaying a spatial resolution of 18.4 lp mm⁻¹, which shows great potential for use in X-ray imaging. In addition, a 3D visual computed tomography (CT) image of a conch was successfully reconstructed, which indicates the fantastic potential of environment-friendly (MPP)₂SbCl₅ in optoelectronic detection applications.