Luminescent Organic Single Crystals for Flexible Optical Fiber Scintillators and X-ray Imaging

Optical fiber-based glass scintillators are high-efficiency scintillators with excellent light collection and transmission properties. However, the performance of optical fiber scintillators is constrained by structural defects in silicate glass and reduced transparency due to doping. To overcome this limitation, we report a high-quality elastic crystal of a Schiff base, (E)-1-(((4-bromophenyl)imino)methyl)naphtha-len-2-ol (BPIN). The one-dimensional crystal exhibits exceptional elasticity and high fracture strength. The dominant π···π interactions and C–H···Br interactions in the crystal contribute significantly to the bending behavior. Moreover, owing to the heavy atom effect that enhances X-ray absorption capability, BPIN demonstrates outstanding scintillation performance with a fast radiative lifetime of 2.90 ns and low detection of 0.11 μGy_air s^–1. Based on the waveguiding and scintillation properties of BPIN, we propose a flexible crystal optical fiber scintillator. Furthermore, by expanding the crystal morphology to two dimensions, a high-resolution X-ray imaging screen is realized. Our study introduces an innovative approach for utilizing organic crystals in high-performance flexible X-ray detectors and imaging.