{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,8]],"date-time":"2026-07-08T01:10:07Z","timestamp":1783473007276,"version":"3.55.0"},"reference-count":40,"publisher":"MDPI AG","issue":"10","license":[{"start":{"date-parts":[[2025,5,8]],"date-time":"2025-05-08T00:00:00Z","timestamp":1746662400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"K2 Center","award":["886385"],"award-info":[{"award-number":["886385"]}]},{"name":"Graz University of Technology","award":["886385"],"award-info":[{"award-number":["886385"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Nanomaterials"],"abstract":"<jats:p>This study examines the impact of Au nanoparticles (Au-NPs) on the chemoresistive gas sensing properties as a function of particle size. The sensing material is composed of ultrathin CuO\/Cu2O films, which are fabricated by either thermal deposition technology or spray pyrolysis. These are used on a silicon nitride (Si3N4) micro hotplate (\u00b5h) chip with Pt electrodes and heaters. The gas sensing material is then functionalised with Au-NP of varying sizes (12, 20, and 40 nm, checked by transmission electron microscopy) using drop coating technology. The finalised sensors are tested by measuring the electrical resistance against various target gases, including carbon monoxide (CO), carbon dioxide (CO2), and a mixture of hydrocarbons (HCMix), in order to evaluate any cross-sensitivity issues. While the sensor response is markedly contingent on the structural surface, our findings indicate that the dimensions of the Au-NPs exert a discernible influence on the sensor\u2019s behaviour in response to varying target gases. The 50 nm thermally evaporated CuO\/Cu2O layers exhibited the highest sensor response of 78% against 2000 ppm CO2. In order to gain further insight into the surface of the sensors, a scanning electron microscope (SEM) was employed, and to gain information about the composition, Raman spectroscopy was also utilised.<\/jats:p>","DOI":"10.3390\/nano15100705","type":"journal-article","created":{"date-parts":[[2025,5,8]],"date-time":"2025-05-08T09:58:09Z","timestamp":1746698289000},"page":"705","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":6,"title":["Investigation of Gas Sensing Performance of CuO\/Cu2O Thin Films as a Function of Au-NP Size for CO, CO2, and Hydrocarbons Mixtures"],"prefix":"10.3390","volume":"15","author":[{"ORCID":"https:\/\/orcid.org\/0009-0009-8963-968X","authenticated-orcid":false,"given":"Christian","family":"Maier","sequence":"first","affiliation":[{"name":"Materials Center Leoben Forschung GmbH, Roseggerstra\u00dfe 12, 8700 Leoben, Austria"},{"name":"Institute for Chemistry and Technology of Materials, Graz University of Technology, Stremayrgasse 9, 8010 Graz, Austria"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6723-9110","authenticated-orcid":false,"given":"Larissa","family":"Egger","sequence":"additional","affiliation":[{"name":"Materials Center Leoben Forschung GmbH, Roseggerstra\u00dfe 12, 8700 Leoben, Austria"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Anton","family":"K\u00f6ck","sequence":"additional","affiliation":[{"name":"Materials Center Leoben Forschung GmbH, Roseggerstra\u00dfe 12, 8700 Leoben, Austria"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"S\u00f6ren","family":"Becker","sequence":"additional","affiliation":[{"name":"Fraunhofer Center for Applied Nanotechnology, Grindelallee 117, 20146 Hamburg, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jan Steffen","family":"Niehaus","sequence":"additional","affiliation":[{"name":"Fraunhofer Center for Applied Nanotechnology, Grindelallee 117, 20146 Hamburg, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Klaus","family":"Reichmann","sequence":"additional","affiliation":[{"name":"Institute for Chemistry and Technology of Materials, Graz University of Technology, Stremayrgasse 9, 8010 Graz, Austria"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2025,5,8]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1","DOI":"10.3390\/chemosensors3010001","article-title":"First Fifty Years of Chemoresistive Gas Sensors","volume":"3","author":"Neri","year":"2015","journal-title":"Chemosensors"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"113578","DOI":"10.1016\/j.sna.2022.113578","article-title":"Nanostructured metal oxide semiconductor-based gas sensors: A comprehensive review","volume":"341","author":"Krishna","year":"2022","journal-title":"Sens. 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