Co-doped NaBiO3 nanosheets with surface confined Co species: High catalytic activation of peroxymonosulfate and ultra-low Co leaching

Abstract

In this study, Co-doped NaBiO3 nanosheets with surface confined Co reactive sites were prepared and utilized to catalyze peroxymonosulfate (PMS) activation and further degrade ibuprofen. Characterization results indicate Co reactive sites were mainly confined in surface region of Co-doped NaBiO3 nanosheets with the atomic percentage of 6.9% on catalyst surface. Further, the system of Co-doped NaBiO3/PMS was constructed for ibuprofen degradation. The added ibuprofen (20 µmol L−1) was removed completely in 30 min in the co-use ofPMS (1 mmol L−1) and Co-doped NaBiO3 (0.2 g L−1) at pH0 7.0. Moreover, ultra-low Co leaching of lower than 5 μg L−1 at pH0 5–10 was observed in 30 min. Thus, Co-doped NaBiO3 exhibited highly catalytic stability for ibuprofen degradation in the neutral solution during the ten successive degradation runs. By identifying reactive oxygen species and degradation intermediates of IBP, IBP degradation pathway mainly induced by the generated sulfate radicals in the system of Co-doped NaBiO3/PMS was proposed. These interesting findings shed some new insight on the design of supported Co catalysts with high catalytic and chemical stability for the oxidative decontamination.