Visible-light photovoltaic effect in multiferroic Bi2Fe4O9 thin film

Ferroelectric photovoltaics have attracted extremely attention due to their unique internal electric field driven by the polarization. Herein, the multiferroic Bi2Fe4O9 microcrystals were synthesized via a facile hydrothermal method and Bi2Fe4O9 thin films were prepared by knife coating. The phase purity, morphology and chemical component of the sample were detected by powder XRD, SEM and EDS tests. A visible-light bandgap about 2.13 eV has been revealed in Bi2Fe4O9. An enhanced bulk photovoltaic effect was observed in poled sample (at 30 kV/cm2) with a steady-state photocurrent of 0.62 µA/cm2 and photovoltage of 0.16 V under the standard AM 1.5G illumination. This finding may offer a promising candidate for potential photoelectric devices.