Multiferroics and electronic structure of (1 − x)PbTiO3-xBi(Ni1/2Ti1/2)O3 thin films

The single phase (1 − x)PbTiO3 - xBi(Ni1/2Ti1/2)O3 thin films were synthesized on Pt/Ti/SiO2/Si substrate at 600 °C by a chemical solution deposition route. The present films exhibit homogeneous and crackfree microstructure with low porosity. The surface roughness decreases from 5.56 nm to 1.62 nm with solubility. The remanent polarization monotonously decreases with the dopant Bi(Ni1/2Ti1/2)O3 increase. The leakage current desity increases when the solubility increases. O K-edge X-ray absorption spectroscopy and valence-band edge X-ray photoelectron spectroscopy were used to study the electronic structure. The results indicated that the change of ferroelectricity might be ascribed to the hybridizations between O 2p and Pb 6s and Ti 3d orbitals. The ferromagnetic behaviors were also observed in the thin films and saturated magnetization raises monotonously with the Ni solubility due to enhanced superexchange interaction. Magnetoelectic effects increases with dopant Bi(Ni1/2Ti1/2)O3 increase.