Controllable synthesis of ScFeO₃ ceramics with microstructural evolution for thin and broadband high-performance microwave absorption

Controlled microstructures play a pivotal role in upgrading the microwave absorption properties of materials. Herein, ScFeO₃ ceramics with a controllable three-dimensional (3D) network structure were prepared by adjusting the sintering temperature. Specifically, the effect of sintering temperature on microstructure and microwave absorption properties were investigated. The results show that ScFeO₃ ceramics with the sintering temperature of 1300 ºC possess the superior dielectric and magnetic loss capabilities for incident microwaves, which attributes to the ideal 3D network microstructure enhancing the impedance matching characteristic. Besides, this unique 3D network microstructure not only provides multiple channels for multiple reflecting and scattering of microwaves, but also offers abundant interfaces to dissipate microwaves. Furthermore, the natural resonance effect efficiently increases the magnetic loss. The optimal ScFeO₃ samples possess the minimum reflection coefficient (RC_min) of − 57.4 dB at 17.44 GHz with a thickness of 2.45 mm and an effective absorption bandwidth (EAB) covering the whole Ku band (5.6 GHz) with a thickness range of 1.35–1.55 mm. It is believed that ScFeO₃ ceramics can be new promising microwave absorption material with thin, broadband, and strong absorption performance.