J. Perego, I. Villa, A. Pedrini, E. Padovani, R. Crapanzano, A. Vedda, C. Dujardin, C. Bezuidenhout, S. Bracco, P. Sozzani, A. Comotti, L. Gironi, M. Beretta, M. Salomoni, N. Kratochwil, S. Gundacker, E. Auffray, F. Meinardi, A. Monguzzi

Nature Photonics 15, pages 393-400 (2021)

Abstract

Scintillators, materials that produce light pulses upon interaction with ionizing radiation, are widely employed in radiation detectors. In advanced medical-imaging technologies, fast scintillators enabling a time resolution of tens of picoseconds are required to achieve high-resolution imaging at the millimetre length scale. Here we demonstrate that composite materials based on fluorescent metal–organic framework (MOF) nanocrystals can work as fast scintillators. We present a prototype scintillator fabricated by embedding MOF nanocrystals in a polymer. The MOF comprises zirconium oxo-hydroxy clusters, high-Z linking nodes interacting with the ionizing radiation, arranged in an orderly fashion at a nanometric distance from 9,10-diphenylanthracene ligand emitters. Their incorporation in the framework enables fast sensitization of the ligand fluorescence, thus avoiding issues typically arising from the intimate mixing of complementary elements. This proof-of-concept prototype device shows an ultrafast scintillation rise time of ~50 ps, thus supporting the development of new scintillators based on engineered fluorescent MOF nanocrystals.