A novel (Ca0.2Nd0.2Gd0.2Ho0.2Bi0.2) (Fe0.9Ti0.1)O3 high-entropy ceramic protective material with electromagnetic wave absorption and (n, γ) radiation shielding performance

The development of multifunctional protective materials with electromagnetic wave absorption and (n, γ) radiation shielding properties is urgently required to guarantee secure functioning of space nuclear power sources. In this work, the multicomponent perovskite ferrites (Ca 0.2 Nd 0.2 Gd 0.2 Yb 0.2 Bi 0.2 )FeO 3 (RE-1), (Ca 0.2 Nd 0.2 Gd 0.2 Ho 0.2 Bi 0.2 )FeO 3 (RE-2), and (Ca 0.2 Nd 0.2 Gd 0.2 Ho 0.2 Bi 0.2 ) (Fe 0.9 Ti 0.1 )O 3 (RE-3) were prepared by the sol-gel method. Through multicomponent regulation, the dipole polarization and interfacial electronic transitions can be affected by the lattice distortion effect, which enhances the electromagnetic wave absorption characteristics. With an effective absorption bandwidth of 2.92 GHz and a minimum reflection loss of −46.94 dB, RE-3 exhibits the most efficient electromagnetic wave absorption of the three manufactured samples. Regarding the shielding of neutrons, the shielding efficiency of the RE-3 (45 wt%)-polypropylene (RE-3/PP 3 ) reached 99.78 %, which is mainly due to the large neutron absorption cross section of the rare-earth element Gd. With respect to the γ-ray protection capabilities, the lead equivalent values for the RE-3/PP 3 composites are 0.5083 mmPb at a 65 keV energy when narrow-band filtered X-rays are used and 1.1977 mmPb at a 1250 keV energy when a 60 Co gamma source is used. These findings indicate that multicomponent regulation can enhance the Compton effect by altering the valence electron coverage space and that rare-earth elements significantly improve the γ-ray shielding effectiveness of a material in the weak absorption region of lead. In this work, the integration of electromagnetic wave absorption and (n, γ) radiation shielding properties was achieved by multicomponent regulation, which provides a novel tactic for the developing multifunctional protective materials used in the field of deep space exploration .