Unlocking radioluminescence in copper cyclic trinuclear complexes.

Conventional scintillators that rely on heavy metals and halides often struggle with high costs, synthetic complexity, toxicity, and afterglow, while organic scintillators suffer from low light yield and complicated synthesis. This study introduces a family of scintillators based on copper(I) cyclic trinuclear complexes that combine strong radioluminescence with low cost, facile synthesis, nontoxicity, and environmental compatibility. Experimental and computational analyses reveal a distinct luminescence mechanism dominated by intermolecular Cu(I)∙∙∙Cu(I) interactions. An unconventional halogen-free strategy substantially enhances the radioluminescence of a methyl-substituted copper(I) trinuclear complex, achieving an exceptional light yield of ~70,475 photons/MeV. Leveraging these properties, a scintillator screen was fabricated, which achieved a spatial resolution exceeding 20.0 line pairs/mm and retained performance over 200 on-off cycles. Moreover, real-time angiography simulations validated its capability for dynamic x-ray imaging. These findings position copper(I) cyclic trinuclear complexes as a promising candidate for next-generation scintillators with strong potential for real-world applications and offer valuable insights for halogen-free radioluminescent materials.