Constructing oriented two-dimensional fish scale-like Gd@MXene barrier walls in polyvinyl alcohol to achieve excellent neutron shielding properties

The increasing utilization of nuclear energy and radiation medicine has urged flexible neutron shielding materials for personal protection. However, it was a challenge to manufacture neutron shielding materials with good flexibility and efficient neutron shielding performance. Herein, a new type of hybrid filler named Gd@MXene nanoflakes were successfully synthesized via one step-hydrothermal reaction and used for efficient neutron shielding, which was composed of two-dimensional (2D) Ti3C2Tx-MXene nanoflakes and zero-dimensional Gd nanoparticles (NPs). Inspired by fish scales, the spin coating method was employed to manufacture the film composed of polyvinyl alcohol (PVA) and Gd@MXene, which aligned random Gd@MXene into oriented 2D fish scale-like barrier walls. The 2D fish scale-like Gd@MXene barrier walls scattered the neutron rays multiple times between the nanoflakes, thereby improving the neutron absorption efficiency of Gd atoms. The film showed excellent neutron shielding performance and thermal conductivity; the neutron shielding rate of 20-Gd@MXene/PVA with a thickness of 62 μm was 3.36 times higher than that of pure PVA. The thermal conductivity of Gd@MXene/PVA was nearly 10 times higher than that of pure PVA. This work introduced a novel film for neutron radiation shielding and had potential applications in personal wearable protective equipment.