Mercury-free sources of VUV/UV radiation: application of modern excimer lamps (excilamps) for water and air treatment

Abstract

This paper reviews recent experimental results concerning the use of modern excilamps (excimer lamps) in photoscience and photochemical technology. The special characteristics of these sources of incoherent vacuum-UV (VUV)/UV radiation are presented and their applications in water and air remediation are discussed. Special attention is paid to the VUV (172 nm)-initiated oxidation and mineralization of organic water and air contaminants. For example, the VUV-initiated production of carbon dioxide and carbon monoxide during 172 nm irradiation of several saturated volatile organic substrates in the gas phase (e. g. methanol, ethanol, 2-propanol, 1,4-dioxane, cyclohexane, and n-hexane) was quantitatively verified by gas chromatography. Depending on the nature of the gaseous substrate and on the flow rate through the excimer-flow-through photoreactor different CO 2 /CO ratios were obtained.Résumé : Cet article revoit les récents résultats expérimentaux sur l'utilisation d'excilampes (lampes excimères) modernes dans la technologie de la science photoélectrique et photochimique. Les caractéristiques spéciales de ces sources de rayonnement incohérent sous vide UV (VUV)/UV sont présentées et leur utilisation pour la réhabilitation de l'eau et de l'air est abordée. Une attention spéciale est apportée à l'oxydation et à la minéralisation initiées par VUV (172 nm) des contaminants organiques dans l'eau et l'air. Par exemple, la production de dioxyde de carbone et de monoxyde de carbone initiée par VUV au cours d'une radioexposition à 172 nm dans plusieurs substrats organiques volatils saturés dans la phase gazeuse (p. ex. méthanol, éthanol, propan-2-ol, 1,4-dioxane, cyclohexane et n-hexane) a été vérifiée quantitativement par chromatographie en phase gazeuse. Différents rapports CO 2 /CO ont été obtenus selon la nature du substrat gazeux et selon le débit à travers le photoréacteur excimère à écoulement continu.Mots-clés : lampes excimères, excilampes, radioexposition à 172 nm, oxydation aux ultraviolets du vide, photominéra-lisation, désinfection aux UV, photoréacteur excilampe à circulation d'échantillon, photoréacteur à écoulement piston, photo-oxydation en phase gazeuse.[Traduit par la Rédaction]

Study of Formation and Decay of Rare-Gas Excimers by Laser- Induced Fluorescence

“…These applications often use dielectric barrier excimer lamps [5][6][7][8][9][10][11]. Optimization of these VUV sources requires numerical modeling associated with experimental characterization.…”

Synthesis and Luminescent Properties of REVO4–REPO4 (RE = Y, Eu, Gd, Er, Tm, or Yb) Heteronanostructures: A Promising Class of Phosphors for Excitation from NIR to VUV

“…[8][9][10] In turn, this makes lanthanoid ions almost irreplaceable components for the generation of visible light in several systems, 11 as well as in devices comprising upconversion 12,13 or downconversion 14 luminescence. Particularly, RE-doped inorganic nanoparticles [15][16][17] display singular luminescent properties that currently find a number of applications, such as the development of excimer lamps for the elimination of Hg in fluorescent tubes, [18][19][20][21] plasma displays with improved resolution, 22,23 light emitting diode (LED) lamps, 24,25 as well as biolabeling materials. 26,27 .…”

Synergistic Water-Treatment Reactors Using a TiO2-Modified Ti-Mesh Filter

“…Interestingly, although without O 3 bubbling, the excimer/TMiP reactor shows the highest k 1 among reactors. We ascribed the results to reactive species and oxidative intermediates generated by VUV photolysis of water as mentioned by Oppenländer et al [24][25][26][27][28]. Hydroxyl radicals and other reactive species are formed by VUV photolysis of water and can directly react with organics due to their strong oxidation potentials.…”