Investigation of photovoltaic response in brownmillerite multiferroic KBiFe2O5 thin film

Abstract

Brownmillerite structured Multiferroic KBiFe2O5 (KBFO) is a promising photoactive material for subsequent optoelectronic applications due to its smaller bandgap and intrinsic polarization. Herein, we reported the preparation, optical and electrical properties of the KBFO thin film. The phase confirmation of KBFO thin film prepared by a simple spin coating technique was characterized by X-ray diffraction (XRD) pattern. The surface morphology as well as thickness of the KBFO thin film deposited on FTO coated glass was identified by scanning electron microscopy (SEM). The bandgap of KBFO film was investigated by UV-Vis spectroscopy which extends visible to the infrared region compared to conventional perovskitestructured ultiferroic. The evidence of photovoltaic responses in KBFO device was explained based on Current-Voltage characteristics under dark as well as visible light illumination. In summary, the intrinsic polarization and photo absorption properties in KBFO could be regarded the material as a suitable candidate for ferroelectric photovoltaic applications