Hits:

Indexed by:期刊论文

Date of Publication:2017-04-20

Journal:JOURNAL OF PHYSICS D-APPLIED PHYSICS

Included Journals:SCIE、EI

Volume:50

Issue:15

ISSN No.:0022-3727

Key Words:sliding DBD; discharge characteristic; nanosecond pulse discharge; VOC degradation

Abstract:In this work, a nanosecond bipolar pulsed voltage coupled with a negative DC component is employed to generate sliding dielectric barrier discharge (DBD) plasma in a three-electrode geometry reactor and improve volatile organic compound (VOC) degradation at room temperature. The effects of the bipolar pulsed voltage (U-+/- pulse) and negative DC voltage (U-DC) on the discharge characteristic, optical characteristic, plasma gas temperature (T-gas), and vibrational temperature (T-vib) are discussed. The horizontal distribution characteristics of the N-2(C-3 IIu -> (BIIg)-I-3) emission intensity, T-gas, and T-vib are also investigated to understand the propagation mechanism of sliding DBD along the dielectric surface. The experimental results reveal that a negative DC component applied to a third electrode can extend the plasma extension region, indicating that the gas ionization is ignited by the nanosecond high-voltage pulse, while charge drift is forced by the surface potential difference caused by the negative high-voltage DC. The T-gas is measured by optical emission spectroscopy related to the rotational bands of N-2(C-3 IIu -> (BIIg)-I-3), and is approximately 375 +/- 5 K under the condition of U (+/- pulse) = 20 kV and U-DC = -20 kV. Compared with typical surface DBD plasma, sliding DBD plasma is quasi-diffusive and distributed more uniformly within the whole discharge gap. Furthermore, both surface DBD and sliding DBD are used for removing toluene from flowing air. It is found that sliding DBD has higher toluene degradation efficiency and energy yield than surface DBD when they are excited by the positive pulsed voltage (U+pulse).