Neutron radiation exposure is one of the main challenges faced during space missions. There is a critical need for advanced lightweight radiation shielding materials. Two-dimensional (2D) boron nitride nanoplatelets (BNNP) are excellent candidates for polymer matrix nanofillers due to their superior neutron shielding and thermal and mechanical properties. Furthermore, the 2D material anisotropic behavior unlocks the potential for composite property tailoring. This study fabricated ultra-lightweight lamellar BNNP foams (density 0.05 g cm^–3 and 97.5% porous) via freeze-drying processing. The neutron shielding effectiveness or mass absorption coefficient of the BNNP foams with walls perpendicular to the direction of the radiation source was 14.47 cm² g^–1, while that of the foam with parallel configuration was only 8.51 cm² g^–1. The orientation-dependent neutron radiation shielding properties were modeled using the Beer-Lambert law for porous composite materials. The BNNP foam in this study has the potential to benefit advanced tailorable radiation shielding technologies for future aerospace missions.

中子辐射暴露是太空任务期间面临的主要挑战之一。迫切需要先进的轻质辐射屏蔽材料。二维 (2D) 氮化硼纳米片 (BNNP) 因其优异的中子屏蔽以及热性能和机械性能而成为聚合物基质纳米填料的绝佳候选者。此外，二维材料的各向异性行为释放了复合材料性能定制的潜力。本研究通过冷冻干燥加工制造了超轻层状 BNNP 泡沫（密度 0.05 g cm ^–3和 97.5% 孔隙） 。壁面垂直于辐射源方向的BNNP泡沫的中子屏蔽效能或质量吸收系数为14.47 cm ² g ^–1，而平行结构泡沫的中子屏蔽效能或质量吸收系数仅为8.51 cm ² g ^–1。使用多孔复合材料的比尔-朗伯定律对方向相关的中子辐射屏蔽特性进行了建模。这项研究中的 BNNP 泡沫有可能使先进的可定制辐射屏蔽技术受益于未来的航空航天任务。