Solvothermal-based synthesis of barium stannate nanosheets coupled with copper manganate nanoparticles for efficient photooxidation of tetracycline under visible light.

Photocatalytic oxidation of antibiotic waste over semiconducting heterojunction photocatalysts is considered eco-friendly because it is simple and operates under light irradiation. In this work, we apply a solvothermal-based process for obtaining high surface area barium stannate (BaSnO) nanosheets followed by adding 3.0-12.0 wt% of spinel copper manganate (CuMnO) nanoparticles to form n-n CuMnO/BaSnO heterojunction photocatalyst after calcination process. The CuMnO-supported BaSnO nanosheets exhibit mesostructure surfaces with a high surface area range of 133-150 mg. Moreover, introducing CuMnO to BaSnO shows a significant broadening in visible light absorption range due to bandgap reduction down to 2.78 eV in 9.0% CuMnO/BaSnO compared to 3.0 eV for pure BaSnO. The produced CuMnO/BaSnO is used for photooxidation of tetracycline (TC) in water as emerging antibiotic waste under visible light. The photooxidation of TC exhibits the first-order reaction model. The specific dose of 9.0 wt% CuMnO/BaSnO at 2.4 gL displays the highest-performed and recyclable photocatalyst for total oxidation of TC after 90 min. This sustainable photoactivity is attributed to the improved light harvesting and charges migration upon coupling between CuMnO and BaSnO.