High-entropy spinel ferrites MFe2O4 (M = Mg, Mn, Fe, Co, Ni, Cu, Zn) with tunable electromagnetic properties and strong microwave absorption

Abstract Ferrites are the most widely used microwave absorbing materials to deal with threat of electromagnetic (EM) pollution. However, lack sufficient dielectric loss capacity is main challenge that limits their applications. To cope this challenge, three high-entropy (HE) spinel-type ferrite ceramics including (Mg 0.2 Mn Fe Co Ni )Fe 2 O 4 , Cu and Zn were designed successfully prepared through solid state synthesis. The results show all HE MFe samples exhibit synergetic magnetic loss. good ability due presence components; while enhanced properties attributed nano-domain, hopping mechanism resonance effect effect. Among spinels, shows best EM wave absorption performance, e.g., its minimum reflection (RL min ) reaches −35.10 dB at 6.78 GHz a thickness 3.5 mm, optimized effective bandwidth (EAB) 7.48 from 8.48 15.96 2.4 mm. Due easy preparation strong dissipation ability, promising as new type materials.