Modification of a rod-shaped Bi-MOF with MoS₂ nanosheets to form a p-n heterojunction for enhanced antimicrobial activity

A novel visible-light-driven type II p-n heterojunction CAU-17/MoS₂ photocatalytic antifouling biocide was prepared and indicated significant inhibition against the most pharmaceutically recognized harmful microorganisms: gram-positive Staphylococcus aureus (S. aureus), gram-negative Escherichia coli (E. coli) and the drug-resistant bacterium methicillin-resistant Staphylococcus aureus (MRSA). The antimicrobial mechanism is attributed to the production of reactive oxygen species (ROS) such as •OH, ¹O₂ due to the photocatalytic properties of CAU-17/MoS₂ heterojunction. The electron-hole complexation efficiency of the nanocomposites was analyzed using photoluminescence spectroscopy and characterized using electron microscope. It was found that the heterojunction structure of the nanocomposites provided multiple charge transfer channels to significantly improve the transporting and separating efficiency for the photo-induced electron-hole pairs, which consequently facilitated the production of ROS. Given the promising antimicrobial effects, further investigation on the broader application of CAU-17/MoS₂ biocides is needed to test the cytotoxicity, as well as the post-bacteriostatic wound healing effect upon animal models.