Preparation of Ca-doped LaFeO3 nanopowders in a reverse microemulsion and their visible light photocatalytic activity

Abstract Nanoparticles of lanthanum ferrite (LaFeO 3 ) and calcium-doped LaFeO 3 (La 1 − x Ca x FeO 3 , x = 0.05–0.20) with perovskite-type structure have been prepared in a reverse microemulsion. Perovskite powder could be obtained at 500 °C for 3 h. The prepared powders were characterized by thermogravimetry-differential thermal analysis (TG-DTA), X-ray diffraction (XRD) and UV–Vis absorption spectroscopy. The visible-light photocatalytic activity of the photocatalysts was tested with methylene blue as an objective decomposition substance using fluorescence light as a visible light resource. The results showed that partial substitution of La 3+ in LaFeO 3 with Ca 2+ could decrease the crystalline size, enhance visible light absorption and improve visible light photocatalytic activity.