High-Temperature Performance of 9,10-Diphenylanthracene Single Crystals for Fast Neutron Detection

Exploring organic single crystals that can reliably operate in high-temperature environments is crucial for advancing fast neutron detection in extreme conditions. In this study, large-sized ( 34 × 20 × 8 mm³) and high-quality 9,10-diphenylanthracene (DPA) single crystals were grown using a seed-assisted temperature-reduced crystallization method. The crystals showed strong thermal stability with a melting point of 252.4 °C. Under γ -ray excitation, the crystals demonstrated a high light yield of 25 776 photons/MeV with excellent linearity over a broad energy spectrum. Their radiation detection performance was systematically investigated under variable temperature conditions. Temperature-dependent pulse height spectrum (PHS) revealed a steady increase in light output from - 20 °C to 10 °C, followed by a significant decrease beyond 50 °C. However, the DPA detector retains 72.1% of its light output at 150 °C compared to 20 °C, demonstrating its excellent performance at high temperatures. Neutron/gamma pulse shape discrimination (PSD) was tested from - 25 °C to 45 °C. At room temperature, the detector achieved a maximum figure of merit (FOM) of 3.82 at 2900 ± 100 keVee. Importantly, across the entire - 25 °C to 45 °C range, the FOM remained above 1.5 for energies above 200 keVee, demonstrating stable PSD performance. These results collectively demonstrate the strong overall performance of DPA single crystals in both light yield and neutron/gamma discrimination. These findings underscore the great potential of DPA single crystals for fast neutron detection in high-temperature environments, establishing them as a valuable material for future applications in extreme conditions.