Preparation of Core–Shell Structure W/Gd2O3 and Study on the Properties of Radiation Protection Materials

W/Polydopamine (PDA) was prepared by adding W powder into the dopamine (DA) solution and adjusting the pH value of the solution. PDA contains several phenolic hydroxyl and amino groups, which provide abundant active sites for the complexation of metal ions. Therefore, we prepared W/Gd2O3 with core–shell structure by self-assembly method and homogeneous precipitation method, respectively. At the same time, polyurethane (PU) coating fabrics with W and Gd2O3 mixed powder and core–shell W/Gd2O3 powder were prepared, and their X-ray protection performance was tested. Results show that compared with W and Gd2O3 mixed powder PU coating fabrics, the protection efficiency and lead equivalent of core–shell structure W/Gd2O3 powder PU coating fabrics against different energy rays are obviously improved. With the increase in incident energy, the protective efficiency of core–shell structure W/Gd2O3 powder PU coating fabric decreases more slowly than that of W/Gd2O3 mixed powder PU coating fabric. When the incident energy is 65–100 keV, the protective efficiency of the core–shell structure W/Gd2O3 powder PU coating fabric is above 60%, showing a good synergistic protective effect. When the incident energy is 83 keV, the X-ray protection efficiency of core–shell W/Gd2O3 powder PU coating fabric is 65.5%, and the lead equivalent is 0.4051 mmPb.