Construction of cubic CaTiO3 perovskite modified by highly-dispersed cobalt for efficient catalytic degradation of psychoactive pharmaceuticals

Abstract

Sulfate radical mediated advanced oxidation processes (SR-AOPs) have emerged as a promising alternative for emerging contaminants degradation. However, high activity and great stability are commonly difficult to juggle, and the structure-activity correlations are still ambiguous. This study constructed the cubic CaTiO3 perovskite modified by highly-dispersed cobalt for peroxymonosulfate (PMS) activation to improve the specific lattice plane exposure and reduce the metal leaching simultaneously. 98% of amitriptyline (AMT) degradation was achieved within 60 min under the condition of 200 mg/L Co0.1-CTO and 100 mg/L PMS. The results indicated that surface Co2+/Co3+ redox couple and lattice oxygen were responsible for PMS activation, and the evolution of ·OH, SO4·- and 1O2 were revealed. According to density functional theory (DFT) calculations, the highly-dispersed Co on cubic surface effectively captured PMS and promoted electron transfer for the generation of ·OH and SO4·-, while more oxygen atoms exposed on Co0.1-CTO(200) surface facilitated the generation of 1O2. Briefly, this study provides a novel strategy of catalyst synthesis in PMS activation for water treatment.