A novel double anion layered photocatalyst Pb4(BO3)2SO4 with enhanced photocatalytic performance for antibiotic degradation

Abstract

The sewage containing tetracycline antibiotics (TCs) does harm to the aquatic environment. Here, a double anion layered material Pb4(BO3)2SO4 (PBS) exhibiting excellent photocatalytic properties for the degradation of TCs under ultraviolet-visible light is reported. The as-prepared PBS shows a superior photocatalytic activity even at a low dosage (50 mg, 0.048 mmol). The removal rates can reach up to 90.6%, 98.4%, 99.6%, and 98.3% on the degradation of TC, OTC, CTC-HCl, and MTC-HCl (50 ppm) in 10 min, which are 7.941, 10.717, 7.259, and 6.761 times than that of TiO2. The staggered interlayer structures formed by the SO4 and BO3 anion groups are facilitated the charge transfer and enhanced degradation efficiency. Scavenger studies have revealed that h+, •O2−, and •OH take part in photocatalytic degradation. The degradation pathways have presented that hydroxylation and demethylation are contributed to the degradation and transformation of antibiotics. The toxicity of antibiotics and their by-products have been estimated by the T.E.S.T. software, which further confirms the decreased environmental risk after photocatalytic degradation. This study shows that the double anions layered photocatalysts have a potential application in the degradation of antibiotics.