A chemical-kinetic model of DBDs in Ar-H2O mixtures

A simplified chemical-kinetic model was applied to Ar-H2O dielectric-barrier discharges (DBDs), presuming that dissociation processes are only due to energy transfer from excited Ar species. Good agreement was obtained between the densities of HO, H-2, and O-2 and experimental data from the literature, whereas a discrepancy for H2O2 could not be explained. The model is useful for designing DBD reactors and process development. Steady-state densities of H atoms increase with decreasing fractions of x H 2 O which should be kept below 0.1% to obtain a large zone of virtually constant and large H-atom density in the DBD reactor, whereas the HO density is hardly affected by x H 2 O. O-2 contaminations must be kept well below 100 ppm in to attain maximum H-atom densities.