Color-Tunable Hot-Exciton Organic Glassy Supramolecular Scintillators Enabled by Host-Guest Co-Melting

Abstract

Organic glassy scintillators are promising for radiation detection owing to their low cost and facile processability. However, their performance is often constrained by insufficient X-ray absorption and scintillation quenching during vitrification from single crystal to glass. Herein, we present a co-melting strategy that integrates a heavy-atom-containing fluorescent host (TPABr) with hot-exciton emitters (DTPA2F, TPE4Br and BTHDMF) to construct color-tunable organic glassy supramolecular scintillators. Notably, the TPABr-DTPA2F glass shows pronounced enhancements over pristine DTPA2F glass, including a ~51% increase in Young's modulus and a ~41% boost in radioluminescence intensity. These improvements arise from enhanced X-ray absorption and efficient host-guest energy transfer, ensuring high exciton utilization efficiency in co-melted glass. Besides, supramolecular interactions further provide a rigid microenvironment that suppresses nonradiative decay and stabilizes molecular packing, thereby maintaining high scintillation efficiency. As the co-melted glass features an ultrafast lifetime of 1.69 ns, a relative light yield of 33,763 photons MeV^-1 and can be processed into > 12 cm² transparent scintillator screen via comelt-quenching. The resulting screen achieves 30.0 lp mm^-1 static X-ray imaging resolution and eliminates afterglow artifacts in dynamic imaging of vascular models and small biological specimens, demonstrating the potential applications for advanced X-ray imaging.