Advanced X/γ‐Ray‐Shielding Materials Enabled by the In Situ Generation of Cerium–Tungsten Nanoparticles Within Regenerated Collagen Fibers

Advanced X- and γ-ray-shielding materials are conventionally designed and fabricated via the uniform dispersion of high-Z elements into the substrate. These soluble high-Z elements considerably reduced the particle size of functional components; however, the as-obtained composites exhibited weak absorption region at 40-80 keV and poor water resistance. To address these issues, such materials are fabricated by introducing cerium and tungsten into regenerated collagen fibers (RCFs) using a "dual impregnation-desolvation" strategy. The uniform dispersion of functional components is achieved via the in situ generation of cerium-tungsten nanoparticles (CeW NPs) under multiple impregnating and desolvating cycles; as a result, the CeW NPs achieved an ultrasmall particle size of 17.15 nm. Benefiting from the ultrasmall particle size and uniform dispersion of CeW NPs, the fabricated CeW-RCF composites exhibit satisfactory X- and γ-ray-shielding capabilities with an ultrahigh mass attenuation coefficient (MAC) of 5.9 cm² g^-1 at 83 keV, higher than that of lead plates. The CeW-RCF composites also exhibit outstanding mechanical strength, low density, and high air permeability, demonstrating their superior wearability. This work provides novel insights into the design and fabrication of advanced X- and γ-ray-shielding materials with high radiation-shielding performance and enhanced wearability.