Tunable Morphology of Bi2Fe4O9 Crystals for Photocatalytic Oxidation

Orthorhombic Bi2Fe4O9 microplatelets and nanosheets were successfully synthesized through a rather facile hydrothermal process. The as-prepared samples were characterized by X-ray diffraction, scanning electron microscopy, transmission electron microscopy, high-resolution transmission electron microscopy, and UV−vis absorption spectra. The photocatalytic activity of the as-prepared samples was evaluated by the degradation of methyl orange under UV and visible irradiation. The Bi2Fe4O9 nanosheets showed high photocatalytic activity toward methyl orange degradation under visible and UV irradiation, while the Bi2Fe4O9 microplatelets were active only under UV irradiation.