Efficient solar-light photocatalytic activity of FeS/S-doped MgO composites for tetracycline removal

Abstract To overcome the poor visible-light harvesting and the inferior charge transfer and separation of MgO, MgO nanosheets were co-modified by S and FeS (FeS/S-MgO) via a high-temperature sulfurized route. Compared with pure S-MgO, FeS/S-MgO exhibited higher photocatalytic capacity for tetracycline hydrochloride (TCH) under solar light irradiation. It’s attributed to the junction interface between FeS and O-defected S-MgO for promoting the transfer and separation of photo-induced carriers and enhancing the visible-light absorption capacity. The photocatalytic activity of FeS/S-MgO was greatly affected by FeS content, TCH concentration, pH, inorganic salts, and quenchers. The optical 3-FeS/S-MgO with a FeS content of 7.94 wt% degrade 97.10% TCH solution of 40 mg L−1, and declined to 94.21% after five cycles under the same conditions. •OH and h+ played the crucial role in 3-FeS/S-MgO assisted photocatalytic system.