Novel atmospheric pressure plasma device releasing atomic hydrogen: Reduction of microbial-contaminants and OH radicals in the air

Hideo Nojima, Rae Eun Park, Jun Hyoun Kwon, Inseon Suh, Junsang Jeon, Eunju Ha, Hyeon Ki On, Hye Ryung Kim, Kyounghui Choi, Kwang Hee Lee, Baik Lin Seong, Hoon Jung, Shin Jung Kang, Shinichi Namba, Ken Takiyama

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A novel atmospheric pressure plasma device releasing atomic hydrogen has been developed. This device has specific properties such as (1) deactivation of airborne microbial-contaminants, (2) neutralization of indoor OH radicals and (3) being harmless to the human body. It consists of a ceramic plate as a positive ion generation electrode and a needle-shaped electrode as an electron emission electrode. Release of atomic hydrogen from the device has been investigated by the spectroscopic method. Optical emission of atomic hydrogen probably due to recombination of positive ions, H+(H2O)n, generated from the ceramic plate electrode and electrons emitted from the needle-shaped electrode have been clearly observed in the He gas (including water vapour) environment. The efficacy of the device to reduce airborne concentrations of influenza virus, bacteria, mould fungi and allergens has been evaluated. 99.6% of airborne influenza virus has been deactivated with the operation of the device compared with the control test in a 1 m3 chamber after 60 min. The neutralization of the OH radical has been investigated by spectroscopic and biological methods. A remarkable reduction of the OH radical in the air by operation of the device has been observed by laser-induced fluorescence spectroscopy. The cell protection effects of the device against OH radicals in the air have been observed. Furthermore, the side effects have been checked by animal experiments. The harmlessness of the device has been confirmed.

Original languageEnglish
Article number026
Pages (from-to)501-509
Number of pages9
JournalJournal of Physics D: Applied Physics
Issue number2
Publication statusPublished - 2007 Jan 21


All Science Journal Classification (ASJC) codes

  • Electronic, Optical and Magnetic Materials
  • Condensed Matter Physics
  • Acoustics and Ultrasonics
  • Surfaces, Coatings and Films

Cite this

Nojima, H., Park, R. E., Kwon, J. H., Suh, I., Jeon, J., Ha, E., On, H. K., Kim, H. R., Choi, K., Lee, K. H., Seong, B. L., Jung, H., Jung Kang, S., Namba, S., & Takiyama, K. (2007). Novel atmospheric pressure plasma device releasing atomic hydrogen: Reduction of microbial-contaminants and OH radicals in the air. Journal of Physics D: Applied Physics, 40(2), 501-509. [026].