Doped Bismuth Ferrite as Ferrophotocatalyts
Astita Dubey, University of Duisburg Essen, Essen, Germany
Ferroelectric materials have substantial application in the field of memory devices, energy harvesting and photovoltaics. BiFeO3 (BFO) is a type-I multiferroic material with noteworthy ferroelectric behaviour at room temperature. The destruction of space inversion symmetry is the origin of ferroelectricity in BFO, which occurs due to asymmetric lobe space of 6s2 lone-pair electrons of Bi3+ ion. The off-centering of Bi-O and Fe-O along [111]c polarization axis affects the polarization of BFO. BFO thin films have larger polarization (~150 μC/cm2) than bulk (~40 μC/cm2) due to a large Fe-O off-centering along the polar axis [001]c. The intrinsic depolarization field of ferroelectric materials work as driving force to mitigate the recombination of photoinduced charge carriers, which is crucial for photocatalysis. Scaling BFO particles size down to nanometer not only increases the total magnetization but its large surface to volume ratio is useful in photocatalysis, photovoltaics, and electrocatalysis. We dope multivalent elements at Fe- and Bi- sites in BFO NPs and investigate their ferroelectric properties via piezoresponse force microscopy (PFM) and probe their photocatalytic activity.