Construction of hierarchical ZnO-NiCo2O4-NiCo2O4 core-shell microstructure with efficient microwave absorption

•A novel ZnO-NiCo2O4-NiCo2O4 core–shell Microstructure was designed with two different morphologies of NiCo2O4.•The NCO-1 shell increased attenuation capability and NCO-2 shell improved impedance matching.•Both strong reflection loss of −59.93 dB and wide absorption bandwidth of 7.04 GHz.•RCS simulation also indicates that ZNN has outstanding MA performance and good practicability.