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Bacterial infection is seriously threatening human health, and the design of high-efficiency and good biocompatibility antibacterial agents is an urgent problem to be solved. However, with the emergence of drug-resistant bacteria, the existing antibacterial agents have low killing efficiency, and the formation of biofilms has further weakened the therapeutic effect. Herein, we constructed an efficient antibacterial system mediated by nearinfrared light for synergistic antibacterial and biofilm dissipation. Specifically, the ZnO/Ti 3 C 2 T x with heterojunction was synthesized by hydrothermal growth of ZnO on the surface of lamellar Ti 3 C 2 T x -MXene. The prepared ZnO/Ti 3 C 2 T x had better photothermal ability than ZnO and Ti 3 C 2 T x , respectively. The local thermal effect can not only destroy the integrity of the bacterial membrane but also promote the release of Zn 2+ ions and further improve the antibacterial performance. ZnO/Ti 3 C 2 T x achieved a 100% sterilization rate (better than either ZnO or Ti 3 C 2 T x ) at 150 μg mL −1 . The biofilm dissipation experiment further proved its excellent biofilm ablation effect. More importantly, the results of in vitro cell culture and animal experiments have demonstrated its good biological safety. In summary, this new type of nanomaterial shows strong local chemical photothermal sterilization ability and has great potential to replace traditional antibacterial agents.

Developing nonmetal-doped mesoporous TiO2 is highly attractive for preparing semiconductor visible photocatalyst with high activities. Here, we prepare N/F co-doped mesoporous TiO2 with high vis-photocatalytic activities by a simple liquid phase deposition process followed by annealing in air using C[Formula: see text]TAB as a bi-functional template (forming mesoporous and providing dopants). N2 adsorption isotherms, low-angle X-ray diffraction (XRD) and transmission electron microscopy (TEM) indicate the formation of wormhole-like mesoporous structure. Wide-angle XRD and high-resolution TEM demonstrate the presence of anatase TiO2 mesopore wall. XPS analyses reveal that N is doped into TiO2 lattice in the forms of substitutional and interstitial N species, and that F is doped into the TiO2 lattice in the form of interstitial F. The mesopore-forming and doping mechanisms are thoroughly discussed based on the bi-function of C[Formula: see text]TAB template. Mesoporous structure results in a high BET surface area of TiO2. High-concentration nitrogen species in anatase lattice and mesoporous structure remarkably increase the visible absorption of TiO2. As a result, the reaction rate constant of MB degradation catalyzed by N/F co-doped mesoporous TiO2 photocatalysts is about 7 times that by P25.

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