A mass spectrometric study of ions extracted from a point-to-plane dc corona discharge in N(2)O at atmospheric pressure

作者：Skalny J D^*; Orszagh J; Mason N J; Rees J A; Aranda Gonzalvo Y; Whitmore T D

来源：Journal of Physics D: Applied Physics , 2008, 41(8): 085202.

DOI：10.1088/0022-3727/41/8/085202

In this paper we report the first study of ions formed in both positive and negative point-to-plane corona discharges fed by N(2)O containing less than 0.1% of H(2)O at atmospheric pressure. Considerable differences were observed in the mass spectra of the ions produced from corona discharges of different polarities. In all the discharges the product ions were observed mainly in the form of clusters. However, in positive corona discharges only four major groups of cluster ions were monitored whereas in all corona discharges operated with negative polarity a much more varied and complex variety of negative ions was observed. The spectrum of positive ions is highly sensitive to the content of water vapour in nitrous oxide with H(3)O(+) center dot(H2O)n clusters ( especially H(3)O+ center dot(H(2)O)(3)) and NO(+) center dot(H(2)O) n clusters being the dominant products. The yield of NO+ center dot(H(2)O) n was found to increase strongly with increasing discharge current while the yield of H(3)O+ center dot(H(2)O) n clusters was reduced. Spectra of ions detected in negative corona discharges contain clusters of NO(2)(-),NO(2)(-),NO(3)(-) ions and also HNO-3 clustered with N(2)O, NO, NO(2), H(2)O and HNO(3). This paper reports how the yield of such ions is influenced by the plasma characteristics and discusses how these results may be explained by physical and chemical processes in the plasma.

• 出版日期2008-4-21