Preparation And Properties Of Bismuth Oxychloride-based Optoelectronic/photodynamic Nanobiological Antibacterial Materials

The outbreak of New Coronary Pneumonia has been full-blown,and research on preventing environmental health problems caused by microorganisms such as bacteria and viruses is imminent.Compared with antibiotics,photodynamic antibacterial inorganic nanomaterials have a broad-spectrum antibacterial ability,and at the same time can well avoid the resistance of bacteria and viruses.However,at present,such materials are difficult to balance the biological activity and antibacterial properties,which is not conducive to use in vivo;secondly,their narrow light absorption range and low photogenerated carrier separation efficiency affect the antibacterial ability.Therefore,the development and design of biocompatible intelligent photo-antibacterial materials and high-efficiency photodynamic antibacterial materials will have important research significance and application value.Controllable external telecommunication stimulation can not only effectively sterilize but also improve cell activity,providing a new way of thinking for the realization of intelligent photodynamic antibacterial materials.To this end,we designed and synthesized Bi OCl nanosheets with good biocompatibility and photoelectric responsiveness.Using the excellent photoelectric responsiveness produced by its anisotropic layered structure,we studied the antibacterial ability and the antimicrobial ability under the action of the light-controlled surface potential Biological phase activity,and explored its application in the intelligent promotion of biological tissue repair;on the other hand,for the shortcomings of Bi OCl light response range and low carrier separation efficiency,we from oxygen vacancies,heterojunctions and lattice matching From the perspective of collaboration,the Bi₂Mo O₆/Bi/OV-Bi OCl ternary composite nano-bioantibacterial material was designed,and its photodynamic antibacterial ability and biological activity were studied.The main findings are as follows:The biologically active molecule mannitol as a solvent,we obtained Bi OCl nanosheets with good dispersibility and hydrophilicity,with a width of approximately100 nm and a thickness of approximately 10 nm.KPFM,surface photovoltage and photocurrent tests showed that the mannitol-modified Bi OCl nanosheets exhibited good and repeatable photoelectric response capabilities.In vitro assay indicates that,under light switch on state,the mannitol modified Bi OCl nanosheets showing high relative surface potential(?82 m V)can kill almost all the bacteria within 30 min;at light switch off state,conversely,the nanosheets with the relative low surface potential(?28 m V)have high bioactivity and can promote BMSCs proliferation.In vivo study indicates that Bi OCl nanosheets with light on/off switch strategy could promote the infectious skin defect regeneration significantly.We have successfully constructed the Z-type heterojunction structure of Bi₂Mo O₆/Bi/OV-Bi OCl through a two-step solvothermal method.VASP calculations indicate that Bi₂Mo O₆ and OV-Bi OCl have suitable energy band matching,and experiments have confirmed that Bi₂Mo O₆/Bi/OV-Bi OCl can achieve full spectrum absorption from ultraviolet light to near infrared light.Photoelectrochemical tests show that compared to Bi OCl nanosheets,the ternary composite antibacterial material exhibits more excellent photogenerated carrier separation ability.Under the irradiation of visible light,Bi₂Mo O₆/Bi/OV-Bi OCl showed good photodynamic antibacterial ability,and could kill almost all of Escherichia coli and Staphylococcus aureus within30 minutes.The CCK-8 and cell death experiments confirmed that,in addition to the antibacterial ability,Bi₂Mo O₆/Bi/OV-Bi OCl also showed good biocompatibility.