Oxygen-vacancy-mediated LaFe1-xMnxO3-δ perovskite nanocatalysts for degradation of organic pollutants through enhanced surface ozone adsorption and metal doping effects.

Here, a series of LaFe1−xMnxO3−δ perovskite nanocatalysts were synthesized and tested for the catalytic ozonation of m-cresol for the first time. The B-site cation is regulated by metal doping, and the resulting LaFe0.26Mn0.74O3−δ with a rhombohedral structure showed excellent catalytic performance and structural stability owing to the abundant oxygen vacancies and the higher Fe2+/Fe3+ and Mn3+/Mn4+ ratios. Theoretical calculations have revealed that the oxygen vacancy has a strong affinity for ozone adsorption, and thus facilitated ozone decomposition by extending the O–O bond. Combined with low-valence Fe2+ and Mn3+ cations, the electron transfer in the catalytic ozonation reaction has been enhanced, which has promoted the production of reactive oxygen species (ROS). Taken together, the degradation pathway of m-cresol was proposed. Additionally, the LaFe0.26Mn0.74O3−δ catalyst remained stable during a 60 h reaction. This study has not only revealed the adsorption/decomposition pathways of ozone using LaFe0.26Mn0.74O3−δ perovskite nanocatalysts but also provided indepth insight into the electron transfer pathway on the surface of nanocatalysts during the process of catalytic ozonation.