Enhanced magnetocapacitance sensitivity in BiFeO3–poly(vinylidene-fluoride) hot pressed composite films

Highlights: ► Different composite films of BiFeO3–poly(vinylidene-fluoride) are synthesized for first time. ► Optical, magnetocapacitance and dielectric properties of different composite films were studied. ► The optical energy band gap is found to be higher than pure BiFeO3. ► A peak in the refractive index was shifting towards lower wavelengths with an increase in the concentration of PVDF. ► The magnetocapacitance of BFO60 film was found more than Nb doped BiFeO3. - Abstract: Optical, magnetocapacitance and dielectric properties of different composite films of BiFeO3–poly(vinylidene-fluoride) (with concentration of BiFeO3; 70, 60, 50 and 40 wt%) are reported here for first time. The grain size was observed to be ∼50 nm by using atomic force microscopy. A peak in refractive index appears at ∼455 nm, which is found to be shifting towards lower wavelengths, while simultaneously the value of the optical energy band gap is found to increase with an increase in the concentration of PVDF in the composite. It was observed that PVDF, which works as matrix, increases the magnetocapacitance. The magnetocapacitance (MC) of BFO60 (BiFeO3; 60 wt%) was found higher than Nb doped BiFeO3, which may be useful for device applications.