Lightweight and Programmable X-ray Shielding Materials: A Synergistic Strategy of Gradient Attenuation and Modular Assembly

To address the challenge that traditional X-ray shielding materials struggle to balance between high shielding efficiency and lightweight flexibility, this study proposes and realizes a novel paradigm: a modular X-ray shielding material based on a “gradient attenuation strategy”. This strategy involves the ordered gradient arrangement of high-Z elements with different K-absorption edges, ensuring that as X-ray photons traverse the material and their energy decays, they consistently remain within the strong absorption region of the subsequent layer, thereby maximizing the shielding efficiency. Simultaneously, the “modular assembly strategy” endows the material with unprecedented “programmable” and “reconfigurable” characteristics, enabling the rapid customization of optimal shielding sequences for varying radiation energy threats. The results confirm that this gradient attenuation strategy significantly enhances both the shielding efficiency and intrinsic mass attenuation coefficient in the medium X-ray energy range (e.g., 48 and 65 keV), exhibiting comprehensive shielding performance superior to that of lead. Furthermore, while achieving high-performance shielding, the material also demonstrates significant lightweight advantages and excellent mechanical properties. The synergistic combination of the gradient attenuation strategy and the modular assembly strategy provides an important theoretical foundation and a novel design approach for developing the next generation of intelligent, efficient, programmable, and lightweight radiation shielding materials.