Fabrication of flower-like ZnFe2O4@SiO2@C@NiO nanochains/reduced graphene oxides as a high-performance microwave absorber

Hierarchical structured ZnFe2O4@SiO2@C@NiO/reduced graphene oxide (ZSCN/RGO) composites were designed and fabricated via a multi-step route. One-dimensional (1D) ZnFe2O4@SiO2 nanochains were fabricated through magnetic-field-induced stöber method. ZnFe2O4@SiO2@phenolic resin nanochains were synthesized through in-situ polymerization and then after high-temperature carbonization ZnFe2O4@SiO2@C (ZSC) nanochains were obtained. 1D ZSCN nanochains with flower-like surface were formed after NiO nanosheets grew irregularly on the surface. Finally, ZSCN/RGO composites with ZSCN nanochains anchoring on RGO nanosheets were successfully synthesized. The morphology, structure, composition and magnetic performance were systematically investigated. Moreover, the microwave absorption (MA) properties of ZSCN nanochains and ZSCN/RGO composites were compared. The results indicate that ZSCN/RGO composites exhibit a minimum reflection loss (RLmin) of −66.38 dB (9.58 GHz) and an effective absorption bandwidth (EAB) of 3.44 GHz (8.12–11.56 GHz) at a thickness of 2.45 mm, due to the synergetic effect between ZnFe2O4, SiO2, carbon, NiO and RGO. •One-dimensional ZnFe2O4@SiO2@C nanochains were synthesized successfully.•The flower-like structure was obtained after NiO nanosheets grew on ZnFe2O4@SiO2@C nanochains by the hydrothermal method.•The microwave absorption mechanism of ZnFe2O4@SiO2@C@NiO/reduced graphene oxide was demonstrated in depth.•The strongest absorption of -66.38 dB and the effective absorption bandwidth of 3.44 GHz can be obtained.