Plasmon-enhanced visible-light photocatalytic antibacterial activity of metal-organic framework/gold nanocomposites

The use of metal-organic frameworks (MOFs) to achieve excellent photocatalytic antibacterial properties has attracted considerable attention. However, insufficient visible light absorption and rapid electron-hole recombination are two crucial issues for the efficient application of MOF nanomaterials. Herein, a novel type of MOF nanocomposite is designed to achieve remarkable visible light photocatalytic antibacterial activity. Due to the strong localized surface plasmonic resonance effect, the introduction of gold nanorods (AuNRs) can effectively improve the visible light absorption of ZIF-8, thus enhancing the production of reactive oxygen species (ROS). Meanwhile, gold nanoclusters (AuNCs) as novel photosensitizers were further integrated into the composites for synergistic generation of ROS under visible light irradiation. As a result, the obtained AuNR@ZIF-8@AuNC nanocomposites showed strong photo-bactericidal activity against Escherichia coli and Staphylococcus aureus under visible light irradiation, owing to the abundant production of ROS. Furthermore, we demonstrated that these AuNR@ZIF-8@AuNC nanocomposites can be easily deposited on the fibers of masks, which exhibited excellent antibacterial properties compared to commercial masks. This study provides a new plasmon-enhanced approach to enhance the photo-bactericidal activity of MOFs for potential application in environmental and biomedical fields. Novel ZIF-8/gold nanocomposites with significantly enhanced ROS generation capability for boosting the photobactericidal activity of MOFs are fabricated by combining the LSPR effect of AuNRs and the photosensitization feature of ultrasmall AuNCs under visible light illumination.