The reaction kinetics of photochemical ozone (O3)
generation in humid air and oxygen (O2) using efficient, narrow band
vacuum ultra violet (VUV) 172 nm xenon excimer lamps is discussed. Trace
amounts of water (H2O) vapor in the process gas leads to hydroxyl (OH)
and hydroperoxy (HO2) radical formation. These radicals drive a
catalytic O3 destruction cycle limiting O3 saturation
concentration. This catalytic O3 destruction cycle was included into a
quantitative kinetic model describing photochemical O3 production.
Experimental O3 saturation concentrations obtained with coaxial VUV
driven photochemical O3 generators compare satisfactorily with the
models predictions.