Molybdenum disulfide (MoS2) nanosheets vertically coated on titanium for disinfection in the dark

Abstract

Previous studies demonstrated that the antibacterial action of molybdenum disulfide (MoS2) is highly dependent on the light-activated potential of reactive oxygen species (ROS) generation; here vertically aligned molybdenum disulfide nanosheets (MoS2, with or without doping of iron) were coated on titanium (Ti) substrates via a one-step hydrothermal reaction, and their excellent activity against both Escherichia coli (E. coli, ATCC 25922) and Staphylococcus aureus (S. aureus, ATCC 25923) was evidenced under dark conditions. Release of MoO42− and generation of MoS2-inspired ROS were found to be the key factors answering for the bactericidal property of the nanosheets. What’s more, iron-doping in terms of FeMoO4 could boost the antibacterial efficacy further, which stems from quick release of Fe2+ and generation of ROS by Fenton-like reactions. Accordingly, it is believed that the dark antibacterial efficacy of the vertically aligned MoS2 nanosheets is guaranteed by uniting ion release and ROS generation. This study provides new insight into design and application of MoS2 coatings for disinfection of biomedical devices, where light is hard to be served. Keywords: Molybdenum disulfide, Antibacterial activity, Iron, Reactive oxygen species, Titanium