Defect engineering in seaweed-like TiO2@carbon nitride strengthening hydroxyl production for thorough elimination of antibiotics.

The co-existence of oxygen and nitrogen vacancies in the seaweed-like fibrous membrane is able to complete degradation of antibiotics due to the strengthened ·OH production. [Display omitted] • The seaweed-like fibrous heterojunction membrane with oxygen vacancies in TiO 2 and nitrogen vacancies in g-C 3 N 4 was successfully fabricated through a HCl-mediated strategy. • The thorough elimination of various antibiotics with enhanced reaction kinetics is achieved under visible light irradiation. • The co-existence of oxygen vacancies and nitrogen vacancies are responsible for O 2 capture, H 2 O 2 generation, and ·OH production. • The flexible membrane is also appropriate for flowing systems. The highly selective production of ·OH to strengthen the mineralization of antibiotics remains a significant scientific challenge. In this work, the seaweed-like fibrous membrane containing oxygen-vacancies in TiO 2 ultrafine nanocrystals and nitrogen-vacancies in g-C 3 N 4 nanosheets, was rationally designed through a HCl-mediated polycondensation strategy. The photocatalytic test confirmed that the dual-defects membrane containing dual defects exhibited highly efficient capacities in removing a variety of antibiotics under visible light and natural light irradiation, which was much stronger than that of single- or none-defective samples. The mechanism analysis displayed that the dual defects were beneficial to migration of photogenerated charges, expansion of Fermi level gap, and capture of oxygen. The strengthened ·OH production was derived from the decomposition of H 2 O 2 , bypassing the high barrier of direct oxidation of H 2 O. This work focuses the key roles of defects in photocatalytic reaction and attempts to present a promising stride towards advancing defect engineering. [ABSTRACT FROM AUTHOR]