Tunable luminescence based on structural regulation in organic antimony halides for X-ray scintillation†
Abstract
Organic antimony halides show high photoluminescence quantum yield (PLQY) due to their compositional and structural tunability, which provides the possibility for developing high quantum yield scintillators. Herein two antimony halides with the general formulae (NYP)2SbCl5 and (NYP)2Sb2Cl8 (NYP = (naphthalene-1-ylmethyl) triphenylphosphine chloride, C29H24PCl) were successfully synthesized. The (NYP)2Sb2Cl8 compound assumes a seesaw dimer [Sb2Cl8]2− geometry, with the highest PLQY value of 19.34% among all known Sb2Cl8-types. The (NYP)2SbCl5 compound assumes a square pyramidal [SbCl5]2− geometry with a PLQY of approximately 75.07%. Furthermore, both components exhibit remarkable thermal and air stability. Under X-ray excitation, the high photo-quantum yield and negligible self-absorption enable (NYP)2SbCl5 to exhibit impressive scintillation performance. Its light yield is approximately 21 500 photons per MeV and its detection limit is as low as 757.51 nGyair s−1. The flexible scintillation screen of (NYP)2SbCl5 enables a high X-ray imaging resolution of 7.77 lp mm−1 with great potential in practical X-ray imaging applications. This study not only reveals the correlation between the high-performance luminescence properties and crystal structure of organic antimony halides but also underscores the promising application prospects of the materials in the field of radiation detection.