Fe-doped LaNi1-xFexO3 perovskite oxides for enhanced visible-light-driven photocatalytic activity

A series of Fe-doped LaNi1-xFexO3 perovskite oxide photocatalytic materials was prepared using a sol-gel method. The phase composition and morphology of LaNi1-xFexO3 samples were characterized via X-ray diffraction, scanning electron microscopy, transmission electron microscopy, X-ray photoelectron spectroscopy, and other analytical methods. The photocatalytic performance of the samples was tested by assessing the degradation rate of methyl orange. According to the results, Fe-doping caused the lattice distortion of the initially cubic of LaNiO3 to a rhombohedral crystal system. In turn, partial substitution of Ni with Fe was found to increase the amount of oxygen vacancies, resulting in the higher mobility of lattice oxygen and thus improving the photocatalytic activity. The best photocatalytic performance was found in a LaNi0.95Fe0.05O3 sample with a 5% Fe dopant concentration. Furthermore, the degradation rate of methyl orange in LaNi0.95Fe0.05O3 within 120 ​min of visible light irradiation was as high as 98.89%, and its good degradation effect even with respect to other organic dyes such as methylene blue and rhodamine B. Finally, LaNi0.95Fe0.05O3 was shown to maintain high photocatalytic activity and excellent recyclability even after numerous operation cycles.