Preparation of surface molecular-imprinted MOFs for selective degradation of tetracycline antibiotics in wastewater

Fe-based metal-organic frameworks (Fe-MOFs) have attracted significant attention as promising photocatalysts for wastewater treatment. In real complex wastewater systems, conventional Fe-MOFs exhibit a poor selectivity and thus cannot effectively prioritize the degradation of highly toxic pollutants. In this research, a novel tetracycline (TC) imprinted photocatalyst (TMIP) was synthesized using surface molecular imprinting technology with NH2-MIL-101(Fe) as the carrier. TMIP demonstrated a remarkable adsorption capacity (>40 mg/g) for four tetracycline antibiotics, surpassing that of the non-imprinted photocatalyst (TNIP). Additionally, the prepared molecularly imprinted photocatalyst exhibited a higher imprinting factor for TC (3.367) than that for three competitive pollutants (ciprofloxacin: 2.389, sulfathiazole: 1.110, sulfamethazine: 1.186). Furthermore, based on the synergy between the selective adsorption of the imprinting layer and the Fenton-like characteristic of the carrier, TMIP exhibited an outstanding degradation efficiency for TC, achieving complete degradation of TC within 20 minutes of visible light irradiation. The degradation selectivity factors of TMIP for ciprofloxacin and sulfathiazole were 1.768 and 4.579, respectively. Our study demonstrated the feasibility of the approach through efficient degradation of TC in lake water, indicating that TMIP has a significant potential for removing target pollutants from wastewater.