Synthesis and photocatalytic property of Ba-doped BiFeO3 nanoparticles

Ba-doped BiFeO₃ (Bi_1-xBa_xFeO₃) nanoparticles have been synthesized by sol-gel process using bismuth nitrate and iron nitrate as sources. X-ray diffraction (XRD) results show that a peak shift toward low angle caused by the Ba doping. Two characteristic peaks of (104) and (110) merging to a single peak was found when the Ba concentration up to 1%. Transmission electron microscope (TEM) images show that the grain sizes of Bi_1-xBa_xFeO₃ decrease substantially with the increasing of Ba content. In comparison with undoped BiFeO₃, relatively strong absorption in visible light region has been observed in the Ba-doped samples. The Bi_0.97Ba_0.03FeO₃ (x=3%) sample shows the best photocatalytic degradation under visible light irradiation. The possible reasons for the high photocatalytic activity have been discussed.