Core-shell CuCo₂S₄ based microspheres composited with carbon black nanoparticles for effective microwave absorption

CuCo₂S₄ with core-shell structure was prepared by ion exchange self-template method, and the microwave absorption property of CuCo₂S₄ with this morphology was studied. At 30% filling, the maximum effective bandwidth is 4.88 GHz (13.12–18 GHz, 2 mm), and the strongest absorption peak is − 25.52 dB (18 GHz, 1.7 mm). In order to optimize the absorption performance of core-shell CuCo₂S₄, conductive carbon black nanoparticles were blended with core-shell CuCo₂S₄ to obtain CuCo₂S₄/C composite. Compared with single-phase CuCo₂S₄ absorber, the maximum effective bandwidth of the composite increased to 6.00 GHz (12.00–18 GHz, 2 mm), and the strongest absorption peak increased to − 52.60 dB (15.42 GHz, 1.9 mm). These results demonstrated that the introduction of small amount of conductive carbon black nanoparticles not only optimize the impedance matching, but also enhance the polarization loss of the composite, therefore, comprehensively improve the microwave absorption performance of the samples.