8-inch nano-polycrystalline hBN for neutron radiography
Siqi Zhu, Xin Zhang, Shuyue Liu, Mingge Jin, Linfeng He, Xingfen JIANG, Jianrong Zhou, Zhijia Sun, Jie Chen, Yongsheng Huang, J.C. Wang, Wei Zheng
Abstract
Abstract Boron-based scintillators have attracted significant attention due to their high thermal neutron capture cross-section. However, large-area pure boron-based scintillators remain unexplored. Here, an 8-inch pure boron-based thermal neutron scintillator—nano-polycrystalline hexagonal boron nitride (NPhBN) film—was successfully fabricated via high-temperature rapid chemical vapor deposition, achieving full-area uniform and highly efficient luminescence. The NPhBN scintillator exhibits a high photoluminescence quantum yield of 42.5% and an ultrafast neutron response time as low as 14.6 ns, which can be attributed to the carrier confinement effect induced by its nano-polycrystalline structure, thereby enhancing carrier radiative recombination. The neutron radiography systems developed based on this scintillator not only enables large-area multi-object imaging but also clearly reveals the internal structure of metals and organics. Through carrier-confined engineering, this work overcomes the performance limitations of boron-based scintillators, offering a novel technological pathway for large-area multi-object neutron radiography.