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[Display omitted] • A Z-scheme Ti-MOF/QDs/ZIS photocatalyst was fabricated. • The Ti-MOF/QDs/ZIS shows outstanding photocatalytic antibiotics degradation performance. • The Ti-MOF/QDs/ZIS exhibits excellent photocatalytic hydrogen evolution activity. • Ti-MOF/QDs/ZIS was very stable and easily recycled for reuse. • A possible mechanism for Ti-MOF/QDs/ZIS photocatalyst was proposed. Herein, a novel all-solid-state Z-scheme NH 2 -MIL-125(Ti)/Ti 3 C 2 MXene quantum dots/ZnIn 2 S 4 (Ti-MOF/QDs/ZIS) photocatalyst was prepared, then applied for photocatalytic antibiotic (tetracycline and sulfamethazine) degradation and hydrogen evolution under visible light. The Z-scheme Ti-MOF/QDs/ZIS photocatalyst afforded very efficient degradation of tetracycline (TC, 96% in 50 min) and sulfamethazine (SMZ, 98% in 40 min), as well as a high rate of hydrogen generation (2931.9 μmol g-1 h−1) under visible light irradiation. Trapping studies showed superoxide radicals (•O 2 −) to be the main active species for antibiotic degradation, with the intermediates formed during antibiotic photo-oxidation identified by liquid chromatography-mass spectrometry. Photocatalyst recycling studies showed the Z-scheme composite photocatalyst to be stable during both antibiotic photodegradation and hydrogen generation experiments. The Ti 3 C 2 MXene quantum dots facilitated electron transfer between the semiconducting components of Z-scheme composite photocatalyst. This work identifies a promising new Z-scheme photocatalyst system for water purification and solar hydrogen production. [ABSTRACT FROM AUTHOR]

• A series of Z-scheme Ti-MOF/Ag/NiFeLDH photocatalysts were successfully fabricated. • Ti-MOF/Ag/NiFeLDH efficiently generated •O 2 − and •OH radicals under photoexcitation. • Aqueous Rhodamine B and Levofloxacin were rapidly degraded by Ti-MOF/Ag/NiFeLDH. • Ti-MOF/Ag/NiFeLDH was very stable and easily recycled for reuse. • Possible photocatalytic mechanism for Z-scheme Ti-MOF/Ag/NiFeLDH photocatalyst was proposed. Z-scheme hetero-structured photocatalysts show outstanding photocatalytic activity in many reactions. In this work, a series of novel Z-scheme photocatalysts were fabricated via the photo-reduction of plasmonic sliver nanoparticles on the surface of NH 2 -MIL-125 (Ti)/NiFe layered double hydroxide (Ti-MOF/NiFeLDH) hybrids. The obtained Ti-MOF/Ag/NiFeLDH composites showed excellent photocatalytic performance under visible light, with the Ag nanoparticles facilitating charge transfer across Ti-MOF/NiFeLDH heterojunctions, thus boosting the photocatalytic activity. At an optimized Ag loading, 95% of Rhodamine B (RhB) degradation was achieved within 50 min and 92% Levofloxacin (LVX) degradation within 70 min. The degradation intermediates of LVX were analyzed by LC-MS and the decomposition pathways were proposed. Further, the Z-scheme Ti-MOF/Ag/NiFeLDH photocatalyst demonstrated outstanding reusability and stability in recycling tests (removal efficiencies of 92% for RhB and 90% for LVX after 5 successive test cycles). Trapping experiments revealed that superoxide radicals (•O 2 −) and hydroxyl radicals (•OH) were two main reactive species formed under visible light, with valence holes (h+) playing a minor role. Results allowed the mechanisms for antibiotic (i.e. LVX) and dye degradation over Ti-MOF/Ag/NiFeLDH to be proposed. This study introduces a new strategy, the combination of MOFs, LDHs and plasmonic Ag nanoparticles, for fabrication of high-performance Z-scheme photocatalysts for the removal of water pollutants. [ABSTRACT FROM AUTHOR]