Multiferroic and magnetoelectric properties of lead-free Ba0.8Sr0.2Ti0.9Zr0.1O3-Ni0.8Zn0.2Fe2O4 composite films with different deposition sequence

Ba0.8Sr0.2Ti0.9Zr0.1O3/Ni0.8Zn0.2Fe2O4(BN) and Ni0.8Zn0.2Fe2O4/Ba0.8Sr0.2Ti0.9Zr0.1O3 (NB) composite film were deposited on Pt/Ti/SiO2/Si substrates by the sol-gel method and spin-coating method. The results show that the deposition sequences of the composite films have significant influence on the ferroelectric, ferromagnetic and magnetoelectric properties of the composite films. Two composite films possess not only good ferroelectric and ferromagnetic properties but good magnetoelectric properties as well. The NB composite film has clear interface between the ferroelectric film and ferromagnetic film and possesses greater magnetoelectric coupling effect than the BN composite film under the same Hbias. The maximum value of αE is 70.14 mV cm−1 Oe−1 was obtained in the NB composite film when Hbias is 638 Oe.