{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,5,15]],"date-time":"2026-05-15T02:52:33Z","timestamp":1778813553525,"version":"3.51.4"},"reference-count":39,"publisher":"MDPI AG","issue":"5","license":[{"start":{"date-parts":[[2018,4,26]],"date-time":"2018-04-26T00:00:00Z","timestamp":1524700800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100003329","name":"Ministerio de Econom\u00eda y Competitividad","doi-asserted-by":"publisher","award":["TEC2015-71663-R"],"award-info":[{"award-number":["TEC2015-71663-R"]}],"id":[{"id":"10.13039\/501100003329","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100000780","name":"European Commission","doi-asserted-by":"publisher","award":["TEC2015-71663-R"],"award-info":[{"award-number":["TEC2015-71663-R"]}],"id":[{"id":"10.13039\/501100000780","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100000782","name":"European Science Foundation","doi-asserted-by":"publisher","award":["COST TD1105"],"award-info":[{"award-number":["COST TD1105"]}],"id":[{"id":"10.13039\/501100000782","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100003741","name":"Catalan Institution for Research and Advanced Studies","doi-asserted-by":"publisher","id":[{"id":"10.13039\/501100003741","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Here we report on the use of pulsed UV light for activating the gas sensing response of metal oxides. Under pulsed UV light, the resistance of metal oxides presents a ripple due to light-induced transient adsorption and desorption phenomena. This methodology has been applied to tungsten oxide nanoneedle gas sensors operated either at room temperature or under mild heating (50 \u00b0C or 100 \u00b0C). It has been found that by analyzing the rate of resistance change caused by pulsed UV light, a fast determination of gas concentration is achieved (ten-fold improvement in response time). The technique is useful for detecting both oxidizing (NO2) and reducing (NH3) gases, even in the presence of different levels of ambient humidity. Room temperature operated sensors under pulsed UV light show good response towards ammonia and nitrogen dioxide at low power consumption levels. Increasing their operating temperature to 50 \u00b0C or 100 \u00b0C has the effect of further increasing sensitivity.<\/jats:p>","DOI":"10.3390\/s18051346","type":"journal-article","created":{"date-parts":[[2018,4,27]],"date-time":"2018-04-27T06:52:23Z","timestamp":1524811943000},"page":"1346","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":20,"title":["Using the Transient Response of WO3 Nanoneedles under Pulsed UV Light in the Detection of NH3 and NO2"],"prefix":"10.3390","volume":"18","author":[{"given":"Oriol","family":"Gonzalez","sequence":"first","affiliation":[{"name":"MINOS-EMaS, Universitat Rovira i Virgili, Avda. Pa\u00efsos Catalans, 26, 43007 Tarragona, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2553-946X","authenticated-orcid":false,"given":"Tesfalem G.","family":"Welearegay","sequence":"additional","affiliation":[{"name":"MINOS-EMaS, Universitat Rovira i Virgili, Avda. Pa\u00efsos Catalans, 26, 43007 Tarragona, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6245-7933","authenticated-orcid":false,"given":"Xavier","family":"Vilanova","sequence":"additional","affiliation":[{"name":"MINOS-EMaS, Universitat Rovira i Virgili, Avda. Pa\u00efsos Catalans, 26, 43007 Tarragona, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6164-4342","authenticated-orcid":false,"given":"Eduard","family":"Llobet","sequence":"additional","affiliation":[{"name":"MINOS-EMaS, Universitat Rovira i Virgili, Avda. Pa\u00efsos Catalans, 26, 43007 Tarragona, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2018,4,26]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1133","DOI":"10.1088\/0957-0233\/8\/10\/014","article-title":"Conductance-transient analysis of thick-flint tin oxide gas sensors under successive gas-injection steps","volume":"8","author":"Llobet","year":"1997","journal-title":"Meas. Sci. Technol."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"13","DOI":"10.1016\/S0925-4005(97)80272-9","article-title":"Qualitative and quantitative analysis of volatile organic compounds using transient and steady-state responses of a thick-film tin oxide gas sensor array","volume":"41","author":"Llobet","year":"1997","journal-title":"Sens. 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