Elucidating energetics and kinetics in environmentally relevant mixed gas plasmas

Understanding energy distributions and kinetic processes in low temperature plasmas is vital to increase their utility for a range of applications, in particular pollution remediation. Optical emission spectroscopy (OES) was employed to elucidate energetic and kinetic trends for several diatomic species in CH4/N2 and CH4/H2O plasma systems. Vast differences in rotational and vibrational temperatures between dissimilar plasma species were observed, indicating the internal temperatures of excited state species are not equilibrated with each other. In combination with energy partitioning results, species formation and destruction rates within the plasma were derived from time-resolved OES data. The results provide insight into molecule formation pathways, including that the formation of CN may be related to excited nitrogen species available in CH4/N2 plasmas.