Relaxor behaviour and photocatalytic properties of BaBi2Nb2O9

Lead‐free Aurivillius phase BaBi2Nb2O9 powders were prepared by solid‐state reaction. Ferroelectric measurements on BaBi2Nb2O9 ceramics at room temperature provided supporting evidence for the existence of polar nanoregions and their reversible response to an external electric field, indicating relaxor behaviour. The photocatalytic degradation of rhodamine B reached 12 % after 3 h irradiation of BaBi2Nb2O9 powders under simulated solar light. Ag nanoparticles were photochemically deposited onto the surface of the BaBi2Nb2O9 powders and found to act as electron traps, facilitating the separation of photoexcited charge carriers; thus, the photocatalytic performance was significantly improved. The present study is the first examination of the photochemical reactivity of a relaxor ferroelectric within the Aurivillius family with polar nanoregions.