Dependence of negative ion formation on inhomogeneous electric field strength in atmospheric pressure negative corona discharge
International Graduate School of Arts and Sciences, Yokohama City University, Yokohama, 236-0027, Japan
Corresponding author: a firstname.lastname@example.org
Revised: 8 November 2008
Published online: 12 December 2008
The dependence of negative ion formation on the inhomogeneous electric field strength in atmospheric pressure negative corona discharge with point-to-plane electrodes has been described. The distribution of negative ions HO-, NOx- and COx- and their abundances on the plane electrode was obtained with a mass spectrometer. The ion distribution on the plane was divided into two regions, the center region on the needle axis and peripheral region occurring the dominant NOx- and COx- ions and HO- ion, respectively. The calculated electric field strength in inhomogeneous electric field established on the needle tip surface suggested that the abundant formation of NOx- and COx- ions and HO- ion is attributed to the high field strength at the tip apex region over 108 Vm-1 and the low field strength at the tip peripheral region of the order of 107 Vm-1, respectively. The formation of HO-, NOx- and COx- has been discussed from the standpoint of negative ion evolution based on the thermochemical reaction and the kinetic energy of electron emitted from the needle tip.
PACS: 52.80.Hc – Glow; corona / 82.33.Xj – Plasma reactions (including flowing afterglow and electric discharges) / 82.30.Fi – Ion-molecule, ion-ion, and charge-transfer reactions / 82.33.Tb – Atmospheric chemistry
© EDP Sciences, Società Italiana di Fisica, Springer-Verlag, 2008