BiFeO3–(Na0.5Bi0.5)TiO3 butterfly wing scales: Synthesis, visible-light photocatalytic and magnetic properties

BiFeO3–(Na0.5Bi0.5)TiO3 (BFO–NBT) with ordered macropores was synthesized from Shirozu butterfly wings by a sol–gel method followed by calcination. The hierarchical structures were retained in the BFO–NBT replica, as evidenced directly by field-emission scanning electron microscope (FE-SEM) and transmission electron microscopy (TEM). The BFO–NBT replica showed a much higher visible-light photocatalytic properties in comparison with BFO–NBT powder without ordered macropores, attributing to the significantly higher surface area. It was found that the magnetic properties of the BFO–NBT replica were quite different with BFO–NBT powder without ordered macropores, probably due to the different grain sizes, and the hierarchical structures from Shirozu butterfly wings. It is expected that our method will open up new avenues for the synthesis of multiferroic materials with hierarchical structures, which may form applications as semiconductor visible-light photocatalyst and novel magnetoelectric devices.