{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,7]],"date-time":"2026-04-07T04:30:00Z","timestamp":1775536200826,"version":"3.50.1"},"reference-count":37,"publisher":"MDPI AG","issue":"11","license":[{"start":{"date-parts":[[2016,10,31]],"date-time":"2016-10-31T00:00:00Z","timestamp":1477872000000},"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>A photoactivated gas detector operated at room temperature was microfabricated using a simple hydrothermal method. We report that the photoactivated gas detector can detect toluene using a UV illumination of 2 \u03bcW\/cm2. By ultraviolet (UV) illumination, gas detectors sense toluene at room temperature without heating. A significant enhancement of detector sensitivity is achieved because of the high surface-area-to-volume ratio of the morphology of the coral-like ZnO nanorods arrays (NRAs) and the increased number of photo-induced oxygen ions under UV illumination. The corresponding sensitivity (\u0394R\/R0) of the detector based on coral-like ZnO NRAs is enhanced by approximately 1022% compared to that of thin-film detectors. The proposed detector greatly extends the dynamic range of detection of metal-oxide-based detectors for gas sensing applications. We report the first-ever detection of toluene with a novel coral-like NRAs gas detector at room temperature. A sensing mechanism model is also proposed to explain the sensing responses of gas detectors based on coral-like ZnO NRAs.<\/jats:p>","DOI":"10.3390\/s16111820","type":"journal-article","created":{"date-parts":[[2016,10,31]],"date-time":"2016-10-31T11:09:46Z","timestamp":1477912186000},"page":"1820","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":10,"title":["A Photoactivated Gas Detector for Toluene Sensing at Room Temperature Based on New Coral-Like ZnO Nanostructure Arrays"],"prefix":"10.3390","volume":"16","author":[{"given":"Li-Ko","family":"Yeh","sequence":"first","affiliation":[{"name":"Graduate Institute of Electronics Engineering, National Taiwan University, Taipei City 10617, Taiwan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jie-Chun","family":"Luo","sequence":"additional","affiliation":[{"name":"Graduate Institute of Electronics Engineering, National Taiwan University, Taipei City 10617, Taiwan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Min-Chun","family":"Chen","sequence":"additional","affiliation":[{"name":"Department of Chemical Engineering, National Taiwan University, Taipei City 10617, Taiwan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Chih-Hung","family":"Wu","sequence":"additional","affiliation":[{"name":"Graduate Institute of Applied Mechanics, National Taiwan University, Taipei City 10617, Taiwan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1071-2234","authenticated-orcid":false,"given":"Jian-Zhang","family":"Chen","sequence":"additional","affiliation":[{"name":"Graduate Institute of Applied Mechanics, National Taiwan University, Taipei City 10617, Taiwan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"I-Chun","family":"Cheng","sequence":"additional","affiliation":[{"name":"Department of Electrical Engineering, National Taiwan University, Taipei City 10617, Taiwan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Cheng-Che","family":"Hsu","sequence":"additional","affiliation":[{"name":"Department of Chemical Engineering, National Taiwan University, Taipei City 10617, Taiwan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Wei-Cheng","family":"Tian","sequence":"additional","affiliation":[{"name":"Graduate Institute of Electronics Engineering, National Taiwan University, Taipei City 10617, Taiwan"},{"name":"Department of Electrical Engineering, National Taiwan University, Taipei City 10617, Taiwan"},{"name":"Graduate Institute of Biomedical Electronics and Bioinformatics, National Taiwan University, Taipei City 10617, Taiwan"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2016,10,31]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"2088","DOI":"10.3390\/s100302088","article-title":"Metal oxide gas sensors: Sensitivity and influencing factors","volume":"10","author":"Wang","year":"2010","journal-title":"Sensors"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"670","DOI":"10.3390\/s100100670","article-title":"A macroporous TiO2 oxygen sensor fabricated using anodic aluminium oxide as an etching mask","volume":"10","author":"Lu","year":"2010","journal-title":"Sensors"},{"key":"ref_3","first-page":"1","article-title":"SnO2 thick films for room temperature gas sensing applications","volume":"106","author":"Khun","year":"2009","journal-title":"J. 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