{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,28]],"date-time":"2026-04-28T05:49:16Z","timestamp":1777355356210,"version":"3.51.4"},"reference-count":77,"publisher":"MDPI AG","issue":"23","license":[{"start":{"date-parts":[[2020,12,1]],"date-time":"2020-12-01T00:00:00Z","timestamp":1606780800000},"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>Undoped and nickel-doped zinc oxide thin films were deposited on sodalime glass substrates by utilizing dip coating and ultrasonic spray pyrolysis deposition techniques. In both cases zinc acetate and nickel acetylacetonate were used as zinc precursor and nickel dopant source, respectively. XRD analysis confirms the ZnO wurtzite structure with (002) as the preferential orientation.SEM studies show the formation of two types of morphologies, primarily a porous spherical grains with a grain size distribution from 40 to 150 nm and another, rose-like structures with size distribution from 30 to 200 nm, based on different deposition techniques utilized. The elemental depth profiles across the films were investigated by the secondary-ion mass spectrometry (SIMS). Different gas sensing responses of all ZnO films were obtained for both propane and carbon monoxide gases, at different gas concentrations and operating temperatures. The highest sensing response (~6) for undoped ZnO films was obtained for films deposited by ultrasonic spray pyrolysis (USP). Nevertheless, the highest sensing response (~4 \u00d7 104) for doped ZnO films was obtained for films deposited by dip coating method. The behavior of sensing responses is explained in detail based on the morphological properties and the amount of Ni impurities incorporated into the crystal lattice.<\/jats:p>","DOI":"10.3390\/s20236879","type":"journal-article","created":{"date-parts":[[2020,12,1]],"date-time":"2020-12-01T20:06:09Z","timestamp":1606853169000},"page":"6879","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":14,"title":["Undoped and Nickel-Doped Zinc Oxide Thin Films Deposited by Dip Coating and Ultrasonic Spray Pyrolysis Methods for Propane and Carbon Monoxide Sensing Applications"],"prefix":"10.3390","volume":"20","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-6071-3892","authenticated-orcid":false,"given":"Tangirala Venkata Krishna","family":"Karthik","sequence":"first","affiliation":[{"name":"Escuela Superior de Tepeji del R\u00edo, Ingenier\u00eda Industrial, Universidad Aut\u00f3noma del Estado de Hidalgo, Avenida del Maestro No. 41 Colonia Noxtongo, Segunda Secci\u00f3n, 42855 Tepeji del R\u00edo, Hidalgo, Mexico"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Mar\u00eda de la Luz","family":"Olvera","sequence":"additional","affiliation":[{"name":"SEES, Departamento de Ingenier\u00eda El\u00e9ctrica, Centro de Investigaci\u00f3n y de Estudios Avanzados del Instituto Polit\u00e9cnico Nacional, CINVESTAV-IPN, 07000 Mexico City, Mexico"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Arturo","family":"Maldonado","sequence":"additional","affiliation":[{"name":"SEES, Departamento de Ingenier\u00eda El\u00e9ctrica, Centro de Investigaci\u00f3n y de Estudios Avanzados del Instituto Polit\u00e9cnico Nacional, CINVESTAV-IPN, 07000 Mexico City, Mexico"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Rajesh Roshan","family":"Biswal","sequence":"additional","affiliation":[{"name":"Escuela de Ingenier\u00eda y Ciencias, Tecnol\u00f3gico de Monterrey, Avenida General Ram\u00f3n Corona 2514 Nuevo M\u00e9xico, 45138 Zapopan, Jalisco, Mexico"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Heberto","family":"G\u00f3mez-Pozos","sequence":"additional","affiliation":[{"name":"\u00c1rea acad\u00e9mica de computaci\u00f3n y electr\u00f3nica, Universidad Aut\u00f3noma del Estado de Hidalgo, 56092 Pachuca, Hidalgo, Mexico"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2020,12,1]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"6031","DOI":"10.1016\/j.ceramint.2013.11.052","article-title":"Structural and dielectric properties of Al-doped ZnOnanostructures","volume":"40","author":"Zamiri","year":"2014","journal-title":"Ceram. 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