Abstract In this study, Ar– \: N₂O discharges sustained by a surfatron device operated at atmospheric pressure were investigated to elucidate their physicochemical behavior and potential for reactive oxygen and nitrogen species (RONS) generation through \: N₂O decomposition. The addition of \: N₂O to an argon plasma led to a shortening of the plasma column and the appearance of a diffuse afterglow region that extends to long distances (> 50 cm). Increasing \: N₂O concentration results in suppression of the discharge filamentation, as well as to an increase in gas temperature, that exceeds 3000 K above 1. 5% \: N₂O. Spectroscopic and thermometric analyses confirmed effective \: N₂O dissociation and the formation of RONS in the discharge. The afterglow, characterized by long-lived metastables and excited argon, nitrogen, and oxygen species, exhibited progressively decreasing temperatures, reaching below 100 °C. Optical emission analysis in this zone revealed rich \: Ar, \: N, \: O, \: NO, \: OH, and \: NH spectra, from which dissociation pathways and kinetic mechanisms have been proposed. A simplified kinetics scheme to elucidate the behavior of these plasmas is proposed, and the results are compared to those obtained with Ar– \: N₂ plasmas and postdischarges. In addition, mass spectrometry suggests \: N₂O decomposition preferentially takes place through nitrogen-oxygen bond breaking, yielding \: N₂, \: O₂, and \: NOₗ products at the gas exhaust.
Morales-Calero et al. (2026) studied this question.