Preparation and properties of the CoFe2O4/Bi3.15Nd0.85Ti3O12 multiferroic composite coaxial nanotubes

The CoFe2O4 (CFO)/Bi3.15Nd0.85Ti3O12 (BNT) multiferroic composite coaxial nanotubes were prepared by a sol–gel template method. The morphologies of the coaxial nanotubes were characterized and the selected area electron diffraction patterns confirmed the coexistence of spinel CFO and perovskite BNT phase. The vibrating sample magnetometer measurements showed that the saturation magnetization and coercive field of the coaxial nanotubes were 1 emu/g and 0.7 kOe, respectively, which was contributed totally from the inner CFO nanotubes. The CFO/BNT coaxial nanotubes showed typical ferroelectric hysteresis loop, while the increased leakage current density is likely due to the high conductivity in the inner CFO nanotubes. Our study demonstrated that the CFO/BNT coaxial nanotubes were of both ferroelectric and magnetic features in nanoscale.

► CoFe2O4(CFO)/Bi3.15Nd0.85Ti3O12(BNT) multiferroic coaxial nanotubes were prepared.
► The coexistence of spinel CFO and perovskite BNT phases was confirmed.
► Both ferroelectricity and ferromagnetism were demonstrated in CFO/BNT nanotubes.
► The ferromagnetism was contributed totally from the inner CFO nanotubes.
► The increased leakage current density comes mainly from the inner CFO nanotubes.