Efficient removal TC by Zn@SnO2/PI via the synergy of adsorption and photocatalysis under visible light

Zn@SnO2/PI material was synthesized by solid-state polymerization and hydrothermal method. The catalyst used for the firstly to remove tetracycline hydrochloride (TC) via the synergistic effect of adsorption and photocatalysis. Zn@SnO2 in the composites provides surface adsorption sites, make the composites have high and rapid adsorption capacity for TC. The PI in the catalyst have good visible light response, which provides the possibility for the composites to have excellent visible light response. Among all the prepared composites, 35Zn@SnO2/PI (the ratio of Zn@SnO2 mass to total mass is 35%, marked as 35Zn@SnO2/PI) has the largest specific surface area (121.77 m2/g) and the largest pore volume (0.167 cm3/g) and has good stability. Meanwhile, the composites of PI and Zn@SnO2 increased the lifetime of electron-hole pairs and heightened the photocatalytic activity of composite for the removal of TC. The results show that the composites can adsorb 40% of TC (20 mg/L, 50 mL) in 30 min under shading reaction. Under visible light irradiation, the removal efficiency of TC can reach 86% in 30 min through adsorption and photocatalysis. Furthermore, the probable photocatalytic removal pathway of TC on Zn@SnO2/PI catalyst was researched based on HPLC-MS analysis. The study may afford a few aiming for the construction of catalysts for the synergistic and efficient treatment of environmental pollutants by adsorption and photocatalysis to solve the increasingly serious environmental problems.