Facile integration of a novel Sm-doped CoFe2O4@ g-CN heterostructure to expedite PMS and H2O2 assisted degradation of pharmaceutical pollutants

Abstract

The persistence of pharmaceutical compounds in the aquatic system has cascading effects on environment and the living world. In order to address the grave concerns regarding pharmaceutical pollution, samarium (Sm) doped cobalt nanoferrite (CS) was merged with a π conjugated carbonaceous material i.e. graphitic carbon nitride (g-CN) to form a series of heterojunction nanocomposites, (CS@x%g-CN) via ultrasonic assisted method. The structure, morphology, magnetic and optical properties of the fabricated nanocomposites were systematically characterized. The synthesized nanocomposites were highly efficient to activate peroxymonosulfate (PMS) and hydrogen peroxide (H2O2) as oxidizing agents for degradation of model pharmaceutical pollutants i.e. levofloxacin, tetracycline, ciprofloxacin and doxorubicin. As compared to H2O2, PMS as oxidant exhibits astonishing results for removal of pollutants. The degradation of tetracycline by employing CS@20 %g-CN (0.25 g/L) nanocomposite as catalyst and PMS (2.2 mM) as oxidant was observed in less than 3 min. Among all, CS@20 %g-CN nanocomposite exhibits highest catalytic activity ascribed to synergistic effect of tunable band structure, high surface area and improved separation of charge carriers across the heterojunction. The newly designed nanocomposites can be recycled up to four catalytic cycles and thus offers a promising strategy in meeting future environmental claims for the removal of refractory compounds from wastewater.