In-situ Mn/Ni dual-metal-anchored ZIF-67 nanocubes for peroxymonosulfate activation toward ofloxacin degradation and photoinactivation.

The present study reports the rational design of a Mn/Ni dual-metal-anchored ZIF-67 photocatalyst (Mn/Ni/ZIF-67) for antibiotic removal and bacterial photoinactivation via peroxymonosulfate (PMS) activation under visible-light irradiation. Structural, morphological, and spectroscopic characterizations (XRD, SEM/TEM, XPS, BET, EPR, PL, and EIS) confirm that Mn and Ni are atomically dispersed within the ZIF-67 nano cubic framework, preserving the parent topology while introducing abundant defect sites and optimized metal-N coordination environments. These features increase the specific surface area, expose more accessible active sites, and facilitate charge separation and interfacial electron transfer, thereby accelerating the generation of SO4•-, •OH, and O2•- as evidenced by radical scavenging tests, quenched PL emission, and reduced charge-transfer resistance. The optimized Mn/Ni/ZIF-67 achieves rapid mineralization of pollutant, ofloxacin (OFX) and high-level inactivation of gram-negative and drug-resistant bacteria within short irradiation times. GC-MS based identification of intermediates enable to elucidate the dominant OFX degradation pathway, while ECOSAR assisted ecotoxicology assessments used to determine the toxic potential of the OFX and the generated intermediates to the model aquatic organisms. The catalyst maintains excellent structural stability, low metal leaching, and high recyclability over multiple cycles, underscoring its practical potential for water disinfection and decontamination. Overall, this work demonstrates that Mn and Ni anchoring in ZIF-67 nanocubes, an effective strategy to engineer visible-light-responsive catalyst, offering a synergistic solution to the dual challenges of chemical remediation and microbial safety in the pursuit of global water security.