Stable Core-Shell UiO-66-NH2@Zeolitic Imidazolate Frameworks Composite as a Favorable Photocatalyst for Tetracycline Degradation

Metal-organic frameworks (MOFs) are promising materials for photocatalytic applications due to their unique properties. Core-shell MOFs have recently emerged as a particularly attractive subclass of MOFs, offering enhanced light absorption, charge separation capabilities, and stability. In this study, we synthesized UiO-66-NH2@ZIF-67 and UiO-66-NH2@ZIF-8 core-shell structures using UiO-66-NH2, ZIF-67, and ZIF-8. We found that UiO-66-NH2@ZIF-67 exhibited a photocatalytic tetracycline (TC) degradation rate that was five times higher than that of pure UiO-66-NH2 under visible light. Furthermore, UiO-66-NH2@ZIF-67 demonstrated superior stability and recyclability, maintaining its efficiency for five cycles. The photocatalytic removal efficiency of TC over UiO-66-NH2@ZIF-67 under visible light reached 97 % in just 60 minutes. In this study, the two MOFs with a high surface area, one with a large bandgap and one with the ability to absorb visible light were combined to construct the desire core-shell structure. Our results offer a novel and convenient strategy for synthesizing highly effective and stable core-shell MOF-on-MOF photocatalysts for photodegradation and TC degradation.