Surface Modified CsPbBr₃ Nanocrystals Enable Free Radical Thermal Polymerization of Efficient Ultrafast Polystyrenic Nanocomposite Scintillators

Abstract

Lead halide perovskite nanocrystals (LHP-NCs) embedded in a plastic matrix are highly promising for a variety of photonic technologies and are quickly gaining attention as ultrafast, radiation-resistant nanoscintillators for radiation detection. However, advancements in LHP-NC-based photonics are hindered by their well-known thermal instability, which makes them unsuitable for industrial thermally activated mass polymerization processes, crucial for creating polystyrene-based scintillating nanocomposites. In this study, we address this challenge by presenting the first thermal nanocomposite scintillators made from CsPbBr 3 NCs passivated with fluorinated ligands that remain attached to the particles surfaces even at high temperatures, enabling their integration into mass-cured polyvinyl toluene without compromising optical properties. Consequently, these nanocomposites demonstrate scintillation light yields reaching 10 400 photons/MeV, subnanosecond scintillation kinetics, and remarkable radiation resilience, able to withstand γ radiation doses of up to 1 MGy. This performance not only meets but also exceeds the scintillation of plastic scintillators despite the radiation-induced damage to the host matrix.