{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,18]],"date-time":"2026-01-18T10:17:44Z","timestamp":1768731464407,"version":"3.49.0"},"reference-count":31,"publisher":"MDPI AG","issue":"4","license":[{"start":{"date-parts":[[2015,3,24]],"date-time":"2015-03-24T00:00:00Z","timestamp":1427155200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"The Ministry of Science and Technology, Taiwan","award":["NSC 102-2221-E-214-003-MY3-1"],"award-info":[{"award-number":["NSC 102-2221-E-214-003-MY3-1"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>The parts-per-billion-level nitric oxide (NO) gas sensing capability of a  copper-ion-doped polyaniline\/tungsten oxide nanocomposite (Cu2+\/PANI\/WO3) film coated on a Rayleigh surface acoustic wave device was investigated. The sensor developed in this study was sensitive to NO gas at room temperature in dry nitrogen. The surface morphology, dopant distribution, and electric properties were characterized using scanning electron microscopy, energy-dispersive X-ray spectroscopy mapping, and Hall effect measurements, respectively. The Cu2+\/PANI\/WO3 film exhibited high NO gas sensitivity and selectivity as well as long-term stability. At 1 ppb of NO, a signal with a frequency shift of 4.3 ppm and a signal-to-noise ratio of 17 was observed. The sensor exhibited distinct selectivity toward NO gas with no substantial response to O2, NH3 and CO2 gases.<\/jats:p>","DOI":"10.3390\/s150407084","type":"journal-article","created":{"date-parts":[[2015,3,24]],"date-time":"2015-03-24T13:07:25Z","timestamp":1427202445000},"page":"7084-7095","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":46,"title":["A Room Temperature Nitric Oxide Gas Sensor Based on a Copper-Ion-Doped Polyaniline\/Tungsten Oxide Nanocomposite"],"prefix":"10.3390","volume":"15","author":[{"given":"Shih-Han","family":"Wang","sequence":"first","affiliation":[{"name":"Department of Chemical Engineering, I-Shou University, Kaohsiung 84001, Taiwan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Chi-Yen","family":"Shen","sequence":"additional","affiliation":[{"name":"Department of Electrical Engineering, I-Shou University, Kaohsiung 84001, Taiwan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jian-Ming","family":"Su","sequence":"additional","affiliation":[{"name":"Department of Electrical Engineering, I-Shou University, Kaohsiung 84001, Taiwan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Shiang-Wen","family":"Chang","sequence":"additional","affiliation":[{"name":"Department of Chemical Engineering, I-Shou University, Kaohsiung 84001, Taiwan"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2015,3,24]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"534","DOI":"10.1016\/j.msec.2005.10.026","article-title":"Amperometric fluidic microchip array sensing device for nitric oxide determination in solution","volume":"26","author":"Wartelle","year":"2006","journal-title":"Mater. 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