Revealing enhanced X-Ray radiation shielding of 2D layered materials and their laminar heterostructures

Abstract

This paper demonstrates a new concept of using two-dimensional (2D) layered materials and their heterostructures for enhanced X-ray radiation shielding. This phenomenon is revealed by characterization on the X-ray shielding performances of several 2D materials with high atomic numbers (Z), including MoS2, antimonene (Sb), and MXene prepared as multi-layered and heterostructure films by assembly their few-layer sheets. Results showed considerable X-ray shielding enhancement of (40–50%) at 30 kVp for individual 2D multi-layered films compared with their bulk structures of these materials. Furthermore, when these multi-layered films were combined into laminar heterostructures structures (e.g., MoS2 + MXene), further enhancement of 60% was achieved. The mechanism of the observed X-ray shielding enhancement by these multi-layered 2D structures is not clear at this stage. It is postulated to be the result of an additional multiple scattering and reflections of photons between multiple layers of 2D crystals inside the film, which does not occur in their uniform bulk materials. The presented results suggest that multi-layered 2D materials with high atomic numbers (Z) and their laminar heterostructures could offer a new and promising strategy for designing of a new generation of Pb-free radiation-shielding materials, which is urgently needed across broad sectors.