Lanthanide-based metal-organic gels for flexible X-ray imaging

Flexible X-ray imaging technology requires scintillators that combine excellent flexibility and high stability. Although traditional inorganic scintillators offer good performance, their brittleness and demanding synthesis conditions limit their applications. In this work, a series of lanthanide-based metal-organic gels (Ln-MOGs, Ln = Tb³⁺, Eu³⁺), named Ln-CPTPY, was prepared through a facile one-pot method at room temperature. Through adjusting molar ratio of Tb³⁺ and Eu³⁺ ions, we achieved tunable emission color from green to red in both photoluminescence and X-ray excited luminescence modes. Upon X-ray irradiation, Ln-MOGs displayed a linear response to X-ray dose rates and good irradiation stability. Notably, the nanoscale MOGs powders were readily dispersed in polydimethylsiloxane without pre-treatment, producing uniform flexible scintillator membranes. These membranes enabled high-resolution X-ray imaging of complex objects, achieving a spatial resolution of approximately 14 lp mm^-1, while their flexibility supported multi-dimensional radio-imaging that displayed the internal structure of flexible devices. This study demonstrates the good potential of Ln-MOGs as multifunctional materials in advanced radio-imaging applications.