Self-Consistent State-to-State Kinetic Modeling of CO2 Cold Plasmas: Insights on the Role of Electronically Excited States.

This study focuses on the role of CO₂ and CO electronically excited states in the kinetics of CO₂ cold non-equilibrium plasma discharges by means of a state-to-state OD kinetic model based on the simultaneous and self-consistent solution of the electron Boltzmann equation and the master equations describing the vibrationally and electronically excited state kinetics and the plasma composition. A new CO₂ dissociation model based on the use of the Biagi electron impact excitation cross sections, considered as fully dissociative, of several CO₂ electronic excited states, in the energy range from 6.5 to 25 eV, is tested and compared with the results obtained by using the Phelps database in typical glow and microwave discharge conditions. Moreover, a refinement of the kinetics of the CO a 3 Π excited state is proposed by including new production and loss terms and the effect of the change of its time evolution density on the eedf, the electron temperature, the CO₂ and CO vibrational distribution functions, electron impact and vibrational induced dissociation rates is investigated. Finally, the contribution of the CO a 3 Π state to CO₂ dissociation is examined in terms of production and recombination (or back-reaction) processes both in microwave and glow discharge conditions. [ABSTRACT FROM AUTHOR]