Theoretical and experimental investigation of blue-emitting plastic scintillators with fast-timing properties

Abstract

Plastic scintillators have been investigated for fast detection with the promise of fast response, ease of scaling up, and mechanical toughness. However, the trade-off between relatively long optical attenuation length and fast timing properties remains complex and challenging. Combining theoretical guidance with experimental verification, a blue-emitting plastic scintillator with faster timing properties is developed by doping benzophenone (BP) into PVT-based plastic scintillators. The intermolecular interaction is identified using symmetry adapted perturbation theory, and the photophysical properties of BP-doped and BP-undoped systems are estimated using first-principles calculations. A shorter fluorescence lifetime is theoretically predicted in the BP-doped system, owing to the relatively higher spontaneous emission decay rate (K_R). The dependence of luminescence performance on the concentrations of fluorescent dyes is uncovered in experiment. The plastic scintillator comprising 6 wt% BP shows a fast decay time of 1.14 ns, shortened by 20% compared to that of the BP-undoped system. Our work offers an approach to design scintillators featuring faster timing properties, expanding the potential applications of blue-emitting scintillators in rapid detection and imaging.