{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,3]],"date-time":"2026-04-03T18:31:18Z","timestamp":1775241078999,"version":"3.50.1"},"reference-count":16,"publisher":"MDPI AG","issue":"22","license":[{"start":{"date-parts":[[2021,11,20]],"date-time":"2021-11-20T00:00:00Z","timestamp":1637366400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Atmospheric photoionization is a widely applied soft ionization mechanism in gas sensing devices for the detection of volatile organic compounds in ambient air. Photoionization is typically induced by low-pressure Vacuum Ultraviolet (VUV) lamps with MgF2 or LiF lamp surface windows depending on the gas fill and the required wavelength transmission window. These lamps are known to exhibit gradually reduced VUV transmission due to hydrocarbon contamination. LiF surface windows are known to be especially problematic due to their hygroscopic nature, reducing VUV lamp lifetime to a mere 100 h, approximately. Here, we present a new design for the electrode of a photoionization detector based on thin-film technology. By replacing the commonplace metal grid electrode\u2019s VUV lamp surface window with a chromium\/gold thin film we obtain a doubling of photon efficiency for photoionization. Replacing the hygroscopic LiF lamp window surface with a metallic layer additionally offers the possibility to vastly increase operational lifetime of low-pressure Argon VUV lamps.<\/jats:p>","DOI":"10.3390\/s21227738","type":"journal-article","created":{"date-parts":[[2021,11,21]],"date-time":"2021-11-21T21:00:50Z","timestamp":1637528450000},"page":"7738","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":9,"title":["Atmospheric Photoionization Detector with Improved Photon Efficiency: A Proof of Concept for Application of a Nanolayer Thin-Film Electrode"],"prefix":"10.3390","volume":"21","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-3957-6288","authenticated-orcid":false,"given":"Adelaide","family":"Miranda","sequence":"first","affiliation":[{"name":"International Iberian Nanotechnology Laboratory, Avenida Mestre Jos\u00e9 Veiga s\/n, 4715-330 Braga, Portugal"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4060-3968","authenticated-orcid":false,"given":"Pieter A. A.","family":"De Beule","sequence":"additional","affiliation":[{"name":"International Iberian Nanotechnology Laboratory, Avenida Mestre Jos\u00e9 Veiga s\/n, 4715-330 Braga, Portugal"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2021,11,20]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"401","DOI":"10.1038\/188401a0","article-title":"A Photoionization Detector for Gases and Vapours","volume":"188","author":"Lovelock","year":"1960","journal-title":"Nature"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"318","DOI":"10.1002\/mas.10060","article-title":"Atmospheric pressure photoionization mass spectrometry","volume":"22","author":"Raffaelli","year":"2003","journal-title":"Mass Spectrom. Rev."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"2493","DOI":"10.1007\/s00216-014-7633-y","article-title":"G. A. Eiceman, Z. Karpas and H. H. 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Opt."}],"container-title":["Sensors"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/1424-8220\/21\/22\/7738\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T07:33:22Z","timestamp":1760168002000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/1424-8220\/21\/22\/7738"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2021,11,20]]},"references-count":16,"journal-issue":{"issue":"22","published-online":{"date-parts":[[2021,11]]}},"alternative-id":["s21227738"],"URL":"https:\/\/doi.org\/10.3390\/s21227738","relation":{},"ISSN":["1424-8220"],"issn-type":[{"value":"1424-8220","type":"electronic"}],"subject":[],"published":{"date-parts":[[2021,11,20]]}}}