Efficient excimer ultraviolet sources from a dielectric barrier discharge in rare‐gas/halogen mixtures

The generation of excimer radiation in mixtures of the rare‐gases Kr or Xe together with chlorine gas has been investigated by a dielectric barrier discharge. The characteristics of the emission spectra of the excimers formed, centered around 222 and 308 nm, were obtained for different gas mixtures and total gas pressures using an ultraviolet (UV) monochromator. The influence of the gas mixture, chlorine gas concentration, total gas pressure, and buffer gas dependence of the UV intensity has been investigated using chemical actinometry. Conversion efficiencies (from input electrical to output optical energy) as high as 15% can be achieved under optimal conditions. This low‐cost and high‐power excimer lamp system can provide an interesting alternative to conventional UV lamps for industrial large‐scale UV processes.