High-throughput imprinted non-metal S-scheme heterojunction self-cleaning membrane with tight adhesion via dopamine for selective photodegradation of TC

Abstract

The traditional photocatalysts have no selective photocatalysis ability and are difficult to separate and recycle. Herein, the imprinted modified non-metal S-scheme heterojunction photocatalytic membrane (IM-NSH-PM) was prepared via imprinting modification technology and dopamine (DA) tight adhesion method, which possessed high throughput (2548.6 L m−2 h−1 bar−1), good self-cleaning performance, excellent stability and recovery performance. The cross-linking and polymerization of DA on PVDF membrane surface can form a strong interaction between basement membrane and imprinted modified non-metal S-scheme heterojunction (IM-NSH), which made IM-NSH-PM adhered closely together. Besides, the formed S-scheme heterojunction between PDI and g-C3N4, which weakened the recombination rate of electrons and holes and further improved the photodegradation ability. The photodegradation rate of TC by IM-NSH-PM reached 71.88%. More importantly, under the action of imprinting modification, IM-NSH was endowed with many imprinted cavities consistent with the three-dimensional structure of tetracycline (TC), thereby TC can be preferentially selective adsorbed and degraded, and the selectivity coefficient of IM-NSH-PM to non-imprinted modified non-metal S-scheme heterojunction photocatalytic membrane (NIM-NSH-PM) was 1.88. This work shows a meaningful idea for exploring self-cleaning membranes with good selective photodegradation ability for the target pollutant.