Giant enhancement of (BH)max in BaFe12O19/Y3Fe5O12 nanocomposite powders

• BaM/YIG nanocomposite powders prepared by the sol–gel method are exchange-coupled.
• The (BH)max of BaM/YIG nanocomposite powders is greatly enhanced.
• An obvious enhancement in remanence of BaM/YIG nanocomposite powders was obtained.

BaFe12O19/Y3Fe5O12 (BaM/YIG) nanocomposite powders were successfully prepared via a simple one-step sol–gel method. All the samples show single-phase-like hysteresis loops indicating the existence of the exchange coupling phenomenon in the nanocomposite powders. Moreover, obvious enhancements of 107.93% in (BH)max value and 19.3% in remanence value can be observed compared with BaM.