In-situ synthesis of flexible aramid nanofiber@CsPbBr3 coaxial fiber-based paper for effective X-ray shielding

Flexible X-ray shielding materials feature better adaptability and dexterity than traditional rigid shielding materials. The effective enhancement of the comprehensive properties of flexible X-ray shielding materials lies in boosting the loading of X-ray absorbing filler while ensuring the retention of their favorable mechanical strength. Here, we designed a Chinese stone arch bridge-like coaxial structure to increase the loading of X-ray absorbing filler CsPbBr₃ in aramid nanofiber (ANF) based composites. The robust and flexible ANF@CsPbBr₃ coaxial fibers were fabricated via coaxial wet-spinning method. The CsPbBr₃ core were rapid in situ crystallized within ANF shell, which achieves the thrilling load capacity for CsPbBr₃ in the material and provides protection against CsPbBr₃ leakage and intrusion of outside moisture, ensuring outstanding X-ray shielding performances. The Chinese stone arch bridge-like structure obtained during spinning effectively prevented collapse of the coaxial fiber shell. Moreover, the ANF@CsPbBr₃ coaxial fibers have excellent flexibility to fabricate an X-ray shielding paper through conventional papermaking process. It also had robust tensile stress (11.8 MPa), lightweight (1.01 g/cm³), excellent X-ray attenuation efficiency (exceed ∼93 % in the 20–70 kV range), and weakened secondary radiation. These findings indicate that the ANF@CsPbBr₃ coaxial fiber have a promising potential for developing X-ray shielding materials.