Time-resolved characterization of non-thermal plasma-assisted photocatalytic removal of nitric oxide

Ming YANG, Kun LIU, Liuhao MA, Kin-Pang CHEONG, Zhen WANG, Wing Kei HO, Wei REN

Research output: Contribution to journalArticle


We performed time-resolved characterization of plasma-photocatalytic removal of nitric oxide (NO) in a ceramic foam packing double dielectric barrier discharge reactor using mid-infrared laser absorption spectroscopy. Non-thermal plasma (NTP) was generated in the porous ceramic foam coated with mesoporous TiO₂ thin film. Real-time NO monitoring was performed using a quantum cascade laser at 5.26 µm combined with a custom-designed multipass gas cell, leading to a sub-ppm detection limit at 0.1 s measurement time. By analyzing the feed gas of 90 ppm NO/1% O₂ balanced in N₂, the plasma treatment without TiO₂ photocatalyst had no effect on NO removal when the discharge power was below 45 W. In comparison, the NTP-TiO₂ system achieved an efficiency of 49% for NO removal even at the relatively low discharge power of 18 W. The synergy between NTP and TiO₂ photocatalyst effectively promotes the NO removal at low plasma discharge powers. However, we also observed a negative effect of TiO₂ photocatalyst on NO removal at a relatively high discharge power of 135 W. Copyright © 2019 IOP Publishing Ltd.
Original languageEnglish
Article number01LT02
JournalJournal Physics D: Applied Physics
Issue number1
Early online dateOct 2019
Publication statusPublished - Jan 2020


Nitric oxide
nitric oxide
Nitric Oxide
Ceramic foams
Quantum cascade lasers
Laser spectroscopy
Infrared lasers
quantum cascade lasers
Time measurement
laser spectroscopy
Absorption spectroscopy
infrared lasers
plasma jets
absorption spectroscopy


Yang, M., Liu, K., Ma, L., Cheong, K.-P., Wang, Z., Ho, W., & Ren, W. (2019). Time-resolved characterization of non-thermal plasma-assisted photocatalytic removal of nitric oxide. Journal of Physics D: Applied Physics, 53(1). Retrieved from https://doi.org/10.1088/1361-6463/ab474b