Optical and electrical properties of ferroelectric Bi0.5Na0.5 TiO3-NiTiO3 semiconductor ceramics

(1-x)Bi0.5Na0.5TiO3-xNiTiO(3) semiconducting ferroelectric ceramics (named (1-x)BNT-xNTO) were successfully prepared by using a solid state reaction method. All samples shows normal polarization-electric field hysteresis loops, and a maximum polarization P max is obtained in the x = 0.06 composition. The diffuse factor y decreases slightly from 1.732 to 1.571 with the addition of NiTiO3. In addition, Ni doping can substantially reduce the band gap of Bi0.5Na0.5TiO3 materials to similar to 2 eV. In a 0.94BNT-0.06NTO compound, the XPS spectra shows that the chemical formula is accurately [Bi0+, Bi3+](0.)(5) Na-0.5[Ti3+, Ti4+]O-2.25-0.06Ni[Ti3+, Ti-4(+)]O-2.67. Moreover, the short-circuit current (J(sc)) in the composition is 1.36 nA/cm(2), and the open-circuit voltaic (V-oc) is 0.35 V for photovoltaic effects. The novel BNT system, which illustrates three narrow band gaps and relatively high polarization values, has broad application prospects for ferroelectric photovoltaic devices.