Montmorillonite and Montmorillonite-Based Composites as Radiation Shielding Materials for Gamma Ray, Ultraviolet Radiation, and Electromagnetic Interference: A Review

With the development of society and the progress of science and technology, all kinds of radiation are getting closer and closer to human life, such as nuclear reactors, medical diagnostic instruments, electronic communication equipment, ultraviolet radiation and so on. Montmorillonite, as a natural two-dimensional layered clay mineral, has abundant reserves, low cost, good environmental compatibility, great ultraviolet reflection/scattering ability, and can provide controllable nano-sized spaces. Meanwhile, it has a high capacity, large specific surface area, good mechanical properties and chemical stability. By acting as additives or carriers, they can meet the shielding requirements of gamma rays, ultraviolet radiation, and electromagnetic interference by modification or composite processes. Herein, the latest research progresses of montmorillonite in gamma ray shielding, ultraviolet radiation shielding, and electromagnetic interference shielding was discussed, and the shielding mechanism of montmorillonite is analyzed. It holds great potential in the development of lightweight, flexible and environmentally friendly shielding materials. Moreover, montmorillonite is usually used as a lightweight filler, dispersion carrier or modifier to enhance the density, dispersity, mechanical properties and thermal stability of shielding materials. However, many challenges and unsolved problems, including further mechanism research, full utilization of montmorillonite, and low-cost and large-scale development methods, deserve further attention and development by researchers. This review has guiding significance for the application of montmorillonite in radiation shielding.