Interface engineered perovskite oxides for enhanced catalytic oxidation: The vital role of lattice oxygen

Advanced oxidation processes are effective ways to eliminate retardant organic pollutants in water. The perovskite oxides, a class of superior catalysts, can effectively activate high-energy material, e.g. peroxymonosulfate, to generate active oxygen species for quickly mineralizing organics. Herein, with the nominal composition of La_xNiO₃ (x = 1.15 and 1.2), nanocomposites composed of LaNiO₃ Single-perovskite and La₂NiO₄ Ruddlesden–Popper are developed through a facile one-pot synthesis. Compared to LaNiO₃, more oxygen vacancies and reactive oxygen species were thus generated for La_1.15NiO₃ and La_1.15NiO₃ exhibits the highest catalytic activity and an excellent stability for contaminants degradation. The performance improvement is mainly attributed to the participation of lattice oxygen, the transformation of oxygen ions and considerable oxygen vacancies. They stimulate the ¹O₂ formation in La_1.15NiO₃ as the main active oxidant. The optimization of perovskites by interface engineering opens a new venue to design efficient catalysts for advanced oxidation processes in environmental treatment.