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Indexed by:期刊论文

Date of Publication:2017-05-01

Journal:PLASMA SOURCES SCIENCE & TECHNOLOGY

Included Journals:SCIE、EI

Volume:26

Issue:5

ISSN No.:0963-0252

Key Words:mesoporous catalyst; particle-in-cell; streamer; dielectric barrier discharge

Abstract:The formation process of a microdischarge (MD) in both ae m-and nm-sized catalyst pores is simulated by a two-dimensional particle-in-cell/Monte Carlo collision model. A parallel-plate dielectric barrier discharge configuration in filamentary mode is considered in ambient air. The discharge is powered by a high voltage pulse. Our calculations reveal that a streamer can penetrate into the surface features of a porous catalyst and MDs can be formed inside both mu m-and nm-sized pores, yielding ionization inside the pore. For the mu m-sized pores, the ionization mainly occurs inside the pore, while for the nm-sized pores the ionization is strongest near and inside the pore. Thus, enhanced discharges near and inside the mesoporous catalyst are observed. Indeed, the maximum values of the electric field, ionization rate and electron density occur near and inside the pore. The maximum electric field and electron density inside the pore first increase when the pore size rises from 4 nm to 10 nm, and then they decrease for the 100 nm pore, due to a more pronounced surface discharge for the smaller pores. However, the ionization rate is highest for the 100 nm pore due to the largest effective ionization region.