Syntheses of Nymphaea-like BiOCl with oxygen vacancies for effective removal of tetracycline hydrochloride

Abstract

Nymphaea-like BiOCl with oxygen vacancies (OVs) was successfully prepared by adjusting the pH of the precursor and using aspartic acid as a surfactant. The as-fabricated samples were investigated by the XRD, SEM, TEM, BET, DRS, PL and SPV techniques. The results reveal that the morphology of the as-prepared samples was self-assembled by thinner nanosheets. Moreover, the sample prepared at pH = 4 can remove 80% of tetracycline hydrochloride (TC, 10 mg L⁻¹) in 1 h. This outstanding photocatalytic performance is attributed to the shorter migration distance of photo-induced carriers due to the thinner nanosheets and the high separation efficiency of photo-generated electron–hole pairs induced by OVs. Furthermore, the dominant free radicals in the present system were identified by trapping experiments and ESR methods. This work provides a new ideal to augment the photocatalytic activity of BiOCl through morphology control and defect engineering.