Preparation, characterization and photocatalytic properties of terbium orthoferrite nanopowder

Perovskite-type terbium orthoferrite (TbFeO3) nanopowder was synthesized through a polyacrylamide gel route. The as-synthesized particles were characterized by XRD, TEM, BET surface area, UV–visible absorption spectroscopy, and XPS. It is shown that the particles are uniformly and regularly shaped like spheres with an average size of ∼50 nm, and have a BET specific surface area of 15.4 m2 g−1. The optical energy bandgap of the nanosized TbFeO3 is obtained to be 1.98 eV. The photocatalytic activity of the TbFeO3 particles was evaluated by the photodegradation of various organic dyes including methyl orange (MO), rhodamine B (RhB), methylene blue (MB), acid fuchsine (AF), and congo red (CR). It is demonstrated that the product exhibits a pronounced photocatalytic degradation of the dyes under visible-light irradiation. The photocatalytic efficiency is observed to depend on the dye type, and under the present experimental conditions it follows the sequence: CR > AF > MB > RhB > MO.