Efficient sterilization by a plasma photocatalytic system(PPS)requires strong synergy between plasma and photocatalyst to inactivate microorganisms while suppressing the formation of secondary pollutants.Here,we repor...Efficient sterilization by a plasma photocatalytic system(PPS)requires strong synergy between plasma and photocatalyst to inactivate microorganisms while suppressing the formation of secondary pollutants.Here,we report that a PPS constructed from a needle array corona discharge and Au/TiO2plasmonic nanocatalyst could remarkably improve the sterilization of Escherichia coli(E.coli)and alleviate formation of the discharge pollutant O3.At 6 kV,the combination of corona discharge and Au/TiO2achieves sterilization efficiency of 100%within an exposure time of 5 min.At 5 kV and an exposure time of 8 min,the presence of Au/TiO2improves sterilization efficiency of the corona discharge from 73%to 91%and reduces the O3concentration from 0.38 to 0.04 ppm,whereas the presence of TiO2reduces the sterilization efficiency and O3concentration to 66%and 0.17 ppm,respectively.The Au/TiO2in the PPS enables a uniform corona discharge,enhances the interaction between plasma,E.coli and nanocatalysts,and suppresses the formation of O3.Further,the Au/TiO2can be excited by ultraviolet-visible light emitted from the plasma to generate electron-hole pairs,and thus contributes to the formation of reactive radicals and the oxidative inactivation of E.coli.The PPS constructed from a needle array corona discharge and Au-based plasmonic nanocatalyst provides a promising approach for developing high-efficiency sterilization techniques.展开更多
基金National Natural Science Foundation of China(Nos.52041001,21808024)Natural Science Foundation of Liaoning Province(No.2020-MS-126)Special Foundation for Key Fields of Colleges and Universities in Guangdong Province(No.2021ZDZX4094)。
文摘Efficient sterilization by a plasma photocatalytic system(PPS)requires strong synergy between plasma and photocatalyst to inactivate microorganisms while suppressing the formation of secondary pollutants.Here,we report that a PPS constructed from a needle array corona discharge and Au/TiO2plasmonic nanocatalyst could remarkably improve the sterilization of Escherichia coli(E.coli)and alleviate formation of the discharge pollutant O3.At 6 kV,the combination of corona discharge and Au/TiO2achieves sterilization efficiency of 100%within an exposure time of 5 min.At 5 kV and an exposure time of 8 min,the presence of Au/TiO2improves sterilization efficiency of the corona discharge from 73%to 91%and reduces the O3concentration from 0.38 to 0.04 ppm,whereas the presence of TiO2reduces the sterilization efficiency and O3concentration to 66%and 0.17 ppm,respectively.The Au/TiO2in the PPS enables a uniform corona discharge,enhances the interaction between plasma,E.coli and nanocatalysts,and suppresses the formation of O3.Further,the Au/TiO2can be excited by ultraviolet-visible light emitted from the plasma to generate electron-hole pairs,and thus contributes to the formation of reactive radicals and the oxidative inactivation of E.coli.The PPS constructed from a needle array corona discharge and Au-based plasmonic nanocatalyst provides a promising approach for developing high-efficiency sterilization techniques.
