Breath moisture-induced electroactive nanofibrous membrane for efficient antibacterial and antiviral air filtration

Abstract

The high humidity environment created by human breath can easily lead to charge loss in the mask's filter and weaken the mask's filtration effect on aerosols containing bacteria and viruses. Therefore, in this study, a breath moisture-induced electroactive nanofibrous membrane was prepared by incorporating Cu/Zn nanoparticles into cellulose acetate/poly (vinyl butyral) fibers. Adjacent Cu/Zn nanoparticles can form galvanic couples that can be activated by human breath to undergo redox discharge reactions, thus imparting moisture-induced electroactivity to nanofibrous membrane. Based on the moisture-induced electroactivity, nanofibrous membrane demonstrated antibacterial rates of 98.32 % against Escherichia coli (E. coli) and 99.06 % against Staphylococcus aureus (S. aureus). Moreover, moisture-induced electroactive nanofibrous membrane significantly reduced the titer of Enterovirus 71 (EV71) transmitted through the respiratory tract within 5 min. The excellent antibacterial and antiviral performance of electroactive nanofibrous membrane can be attributed to the synergistic effect of Cu/Zn’s electrical stimulation (ES) interference on the electrodynamics of bacteria and viruses, the generated reactive oxygen species (ROS), and the released metal ions. Benefiting from the increased surface potential from Cu/Zn galvanic couples, moisture-induced electroactive nanofibrous membrane exhibited a filtration efficiency of 99.61 % for PM_0.3 particles while maintaining a low-pressure drop (78 Pa). Meanwhile, electroactive nanofibrous membrane showed excellent wear comfort and non-cytotoxicity. In summary, this moisture-induced electroactive nanofibrous membrane maintains high filtration performance and exhibits excellent antibacterial and antiviral activities, shedding some light on developing novel efficient air filters.