Inactivation Efficiency of Bioaerosols Using Carbon Nanotube Plasma

The purpose of this study was to inactivate indoor bioaerosols using carbon nanotube corona discharge plasma technology. Escherichia coli, Bacillus subtilis, and λ virus bioaerosols were generated using a Collison nebulizer. The effect of various factors, including the flow rate (30, 60, and 90 lpm) and the operating voltages (−1.5, −3.0, −4.5, −6.0, and −7.5 kV), on bioaerosol reduction was examined. The results indicated that the corona discharge using the carbon nanotube electrodes decreased the threshold voltage of plasma. The inactivation efficiencies of E. coli bioaerosols using the carbon nanotube corona discharge system at discharge voltages of −1.5, −3.0, −4.5, −6.0, and −7.5 kV were 57, 61, 71, 93, and 97%, respectively. The corona discharge system using carbon nanotube electrodes had higher bioaerosol inactivation efficiency than the corona discharge system using stainless steel electrodes. The results further demonstrated that the inactivation efficiency decreased with an increasing flow rate. The inactivation efficiencies of E. coli, B. subtilis, and λ virus bioaerosols using carbon nanotube corona discharge plasma were 93, 88, and 81%, respectively. The results show that using a carbon‐nanotube as a discharge electrode in the corona discharge plasma system can decrease the threshold voltage of plasma generation. In addition, the carbon nanotube corona discharge plasma technology had a significantly higher bioaerosol inactivation efficiency compared to stainless steel electrodes.