Epitaxial Growth of Metal-Organic Framework Thin-Film Scintillators for Temperature-Adaptive, High-Resolution X-Ray Imaging.

Solution-processed scintillators are attractive for large-area X-ray imaging. However, their performance in thin-film architectures is constrained by low effective density, severe light scattering, and insufficient thermal stability. Here, we report a solution-processed epitaxial growth strategy to fabricate large-area, monolithic metal-organic framework (MOF) thin-film scintillators for temperature-adaptive, high-resolution X-ray imaging. Mechanistic investigation reveals that surface hydroxyl-mediated, molecularly oriented epitaxial growth reconstructs the interfacial energy landscape, enabling optically continuous, densely packed terbium-terephthalate (Tb-BDC) films on solid substrates. The Tb-BDC scintillator demonstrates a light yield of 44,380 photons MeV-1 and exceptional thermal stability in scintillation performance. At 513 K, it retains 95.2% of its room-temperature radioluminescence intensity, surpassing the 42.6% retained by commercial Gd2O2S:Tb. Furthermore, it maintains 93.7% of its initial radioluminescence intensity following cumulative X-ray irradiation up to 67.4 Gy. Notably, its radioluminescence intensity remains within 3.6% of the pristine value after 24 h immersion in water. By integrating self-supervised machine learning-assisted image reconstruction, temperature-adaptive X-ray imaging with a spatial resolution of 21.7 lp mm-1 is achieved. This work establishes an epitaxial microstructural design paradigm for solution-processed scintillator screens operating under demanding thermal conditions.