One-step synthesized Zn-doped UiO-66 for effective removal of tetracycline hydrochloride from wastewater

A high adsorption capacity and excellent recyclability are the most critical factors for large-scale application of adsorbents. In this work, a regenerable Zn-UiO-66 was synthesized by doping Zn into UiO-66. The resulting adsorbent exhibited a high adsorption performance for TCH with a qmax of 178.9 mg g−1 at 30 °C and maintained stable adsorption performance across a broad pH range (3–11). The adsorption kinetics and thermodynamics of TCH, together with the zeta potential of the adsorbent under different pH conditions, further confirm the underlying adsorption mechanism, which is proceeded via monolayer chemisorption, primarily governed by π–π conjugation, π–cation interactions, coordination interactions and hydrogen bonding. The adsorbent also performed well in real water matrices. Importantly, Zn-UiO-66 exhibits good water stability and excellent recyclability, with only a slight decrease in adsorption capacity after five cycles using simple water rinsing, underscoring its strong potential for efficient antibiotic removal.