Straddle-type heterostructure films endow titanium implant with NIR photocatalysis property for rapid sterilization

Near-infrared (NIR) light-triggered photocatalysis antibacterial therapy has attracted significant attention. Herein, we designed a straddle-type heterostructure film of ZnS/Ag2S nanorod on the titanium implant, which showed excellent NIR photocatalytic ability. Under NIR, the electrons of Ag2S cascaded jump to ZnS conduction band (CB), and the electron of ZnS was half-jumped to Ag2S valence band (VB). The VB of Ag2S acted as a consumption platform for the holes of Ag2S and the electrons of ZnS, improving photocatalytic efficiency. To prove the feasibility of this mechanism, another straddle-type heterostructure of ZnS/Bi2S3 with similar energy band structure was fabricated, and its NIR photocatalytic ability was also distinctly enhanced. Furthermore, the ZnS/Ag2S heterostructure films rapidly removed bacteria in vitro and in vivo under the NIR irradiation. This work innovatively discovered NIR photocatalytic effect of the straddle-type heterostructure, which complemented the design of heterostructures in photocatalysis.