BaTiO₃@C Core–Shell Nanoparticle/Paraffin Composites for Wide-Band Microwave Absorption

BaTiO3@C nanoparticles with a core–shell nanostructure were synthesized through a facile hydrothermal and dopamine carbonization process. The microstructure of nanoparticles and microwave absorption performance of the nanoparticle/paraffin composite were systematically investigated. Dense heterogeneous interfaces and conductive carbon shells are formed on the surfaces of the BaTiO3 nanoparticles. The enhanced interfacial polarization, dipole polarization, and conductive loss contribute to the improved microwave absorption properties with a minimum reflection loss of −27.1 dB (>99.9% microwave absorption) and a broad bandwidth of 6.0 GHz at a thickness of only 1.8 mm. This work suggests a feasible approach for the efficient production of core–shell-structured nanoparticles with excellent absorption properties.