Solar-light-driven LaFe x Ni 1− x O 3 perovskite oxides for photocatalytic Fenton-like reaction to degrade organic pollutants

Abstract

LaFe x Ni 1− x O 3 perovskite oxides were prepared by the sol–gel method under various conditions, including different pH values (pH 0 and pH 7) and different calcination temperatures (500–800 °C) as well as different Fe/Ni ratios (1/9, 3/7, 5/5, 7/3, 9/1). The samples were examined by XRD, DRS, BET, and SEM to reveal their crystallinity, light-absorption ability, specific surface area, and surface features, respectively. The photocatalytic Fenton reaction was conducted using various LaFe x Ni 1− x O 3 perovskite oxides to decompose the methylene blue molecules. Accordingly, the synthesis condition of pH 0, calcination temperature at 700 °C, and Fe/Ni ratio = 7/3 could form LaFe 0.7 Ni 0.3 O 3 perovskite oxides as highly efficient photocatalysts. Moreover, various conditions during the photocatalytic degradation were verified, such as pH value, catalyst dosage, and the additional amount of H 2 O 2 . LaFe 0.7 Ni 0.3 O 3 perovskite oxides could operate efficiently under pH 3.5, catalyst dosage of 50 mg/150 mL, and H 2 O 2 concentration of 133 ppm to decompose the MB dye in the 1st order kinetic rate constant of 0.0506 s −1 .