Synergy of Organic and Inorganic Sites in 2D Perovskite for Fast Neutron and X-Ray Imaging

Fast neutron and X-ray imaging are considered complementary nondestructive detection technologies. However, due to their opposite cross-sections, development of a scintillator that is sensitive to both fast neutrons and X-rays within a single-material framework remains challenging. Herein, an organic–inorganic hybrid perovskite (C₄H₉NH₃)₂PbBr₄ (BPB) is demonstrated as a scintillator that fully meets the requirements for both fast neutron and X-ray detection. The hydrogen-rich organic component acts as a fast neutron converter and produces detectable recoil protons. The heavy atom-rich inorganic fraction efficiently deposits the energy of charged recoil protons and directly provides a large X-ray cross-section. Due to the synergy of these organic and inorganic components, the BPB scintillator exhibits high light yields (86% of the brightness of a commercial ZnS (Ag)/⁶LiF scintillator for fast neutrons; 22 000 photons per MeV for X-rays) and fast response times (τ_decay = 10.3 ns). More importantly, energy-selective fast neutron and X-ray imaging are also demonstrated, with high resolutions of ≈1 lp mm⁻¹ for fast neutrons and 17.3 lp mm⁻¹ for X-rays; these are among the highest resolution levels for 2D perovskite scintillators. This study highlights the potential of 2D perovskite materials for use in combined fast neutron and X-ray imaging applications.