Modulating charge transfer over metal–organic framework nanocomposites for NIR light-boosted photothermal conversion

Abstract

The controllable charge transfer of light-responsive MOF systems is highly desirable to realize high-efficiency photothermal conversion and improves the understanding of the intrinsic features in natural photosynthetic systems. Mature biofilms can cause serious biofouling endangering public safety; however, classical antibiotics are inefficient to treat adherent bacteria due to serious drug resistance. Photothermal antibacterial agents are a feasible method for the biofilm treatment but are limited in their lower photothermal conversion efficiency and unrepeatable usage. In this work, a NIR light-activated photothermal bacterial nanocomposite (PCN-Mo) was synthesized by modulating the charge transfer between the classical photoactive MOF host and Keggin-type polyoxometalate electron reservoir. The as-synthesized PCN-Mo and its nanoscale form (NPCN-Mo) exhibit great improvement in NIR absorption and boosting the photothermal property in comparison with the prototype PCN-222. Under irradiation at 808 nm, NPCN-Mo shows broad-spectrum antibacterial performance against model S. aureus/E. coli and the formed biofilms. Additionally, self-supporting mix-matrix membranes and antibacterial coatings under various substitutes were fabricated by mixing NPCM-Mo nanoparticles and biodegradable polymers to realize the synergetic properties in both anti-adhesion and antibacterial for renewable usage. This charge transfer strategy in the synthesis of PCN-Mo composite supplies a practical approach in the development of functional light-responsive systems.