Core-shell CoTiO3@MnO2 heterostructure for the photothermal degradation of tetracycline

The photothermal process exhibits the largest energy conversion efficiency among all solar energy utilization processes. In this study, a core-shell CoTiO3@MnO2 (CTM) composite photothermal catalyst was synthesized by supporting MnO2 on CoTiO3 by hydrothermal synthesis. Binding to peroxymonosulfate (PMS) heterogeneous catalyst removed tetracycline in wastewater. The new catalyst was characterized by FT-IR, UV-Vis, XRD, BET, SEM, TEM, and so on. Kinetic analysis showed that CTM activated PMS at a rate of 3.2 and 3.5 times higher than that of pure light and heat conditions, with complete degradation of tetracycline (TC). Since the outer MnO2 layer converted the absorbed solar energy into thermal energy, PMS was activated to generate active species while performing electron transfer, which resulted in a considerably improved catalytic efficiency. To prove the wide applicability of the catalyst, other pollutants were degraded, including bisphenol A (BPA), metronidazole (MNZ), and methyl orange (MO). The three pollutants were degraded within 40 min. Finally, our findings demonstrated the mechanism of the photothermal degradation process and provided a novel approach for environmental remediation using renewable solar energy.

Automated summary

In this study, a core-shell CoTiO3@MnO2 composite photothermal catalyst was synthesized and used for the degradation of tetracycline in wastewater. The catalyst showed significantly improved catalytic efficiency by activating peroxymonosulfate and effectively converting solar energy into thermal energy. The wide applicability of the catalyst was demonstrated by its ability to degrade other pollutants within a short time.