{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,3]],"date-time":"2026-03-03T23:54:48Z","timestamp":1772582088030,"version":"3.50.1"},"reference-count":45,"publisher":"MDPI AG","issue":"13","license":[{"start":{"date-parts":[[2023,6,30]],"date-time":"2023-06-30T00:00:00Z","timestamp":1688083200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Marie Sk\u0142odowska-Curie Actions (MSCA) Research and Innovation Staff Exchange (RISE)","award":["PDC2022-133967-I00"],"award-info":[{"award-number":["PDC2022-133967-I00"]}]},{"name":"Marie Sk\u0142odowska-Curie Actions (MSCA) Research and Innovation Staff Exchange (RISE)","award":["2021 SGR 00147"],"award-info":[{"award-number":["2021 SGR 00147"]}]},{"name":"Marie Sk\u0142odowska-Curie Actions (MSCA) Research and Innovation Staff Exchange (RISE)","award":["PRE2019-087854"],"award-info":[{"award-number":["PRE2019-087854"]}]},{"name":"MICINN","award":["PDC2022-133967-I00"],"award-info":[{"award-number":["PDC2022-133967-I00"]}]},{"name":"MICINN","award":["2021 SGR 00147"],"award-info":[{"award-number":["2021 SGR 00147"]}]},{"name":"MICINN","award":["PRE2019-087854"],"award-info":[{"award-number":["PRE2019-087854"]}]},{"name":"Catalan Institute for Advanced studies (ICREA)","award":["PDC2022-133967-I00"],"award-info":[{"award-number":["PDC2022-133967-I00"]}]},{"name":"Catalan Institute for Advanced studies (ICREA)","award":["2021 SGR 00147"],"award-info":[{"award-number":["2021 SGR 00147"]}]},{"name":"Catalan Institute for Advanced studies (ICREA)","award":["PRE2019-087854"],"award-info":[{"award-number":["PRE2019-087854"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>This paper investigates the effect of decorating graphene with zinc oxide (ZnO) nanoparticles (NPs) for the detection of NO2. In this regard, two graphene sensors with different ZnO loadings of 5 wt.% and 20 wt.% were prepared, and their responses towards NO2 at room temperature and different conditions were compared. The experimental results demonstrate that the graphene loaded with 5 wt.% ZnO NPs (G95\/5) shows better performance at detecting low concentrations of the target gas than the one loaded with 20 wt.% ZnO NPs (G80\/20). Moreover, measurements under dry and humid conditions of the G95\/5 sensor revealed that the material is very sensitive to ambient moisture, showing an almost eight-fold increase in NO2 sensitivity when the background changes from dry to 70% relative humidity. Regarding sensor selectivity, it presents a significant selectivity towards NO2 compared to other gas compounds.<\/jats:p>","DOI":"10.3390\/s23136055","type":"journal-article","created":{"date-parts":[[2023,7,3]],"date-time":"2023-07-03T00:53:16Z","timestamp":1688345596000},"page":"6055","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":19,"title":["ZnO-Loaded Graphene for NO2 Gas Sensing"],"prefix":"10.3390","volume":"23","author":[{"given":"Mohamed Ayoub","family":"Alouani","sequence":"first","affiliation":[{"name":"Microsystems Nanotechnologies for Chemical Analysis (MINOS), Universitat Rovira i Virgili, Avda. Pa\u00efsos Catalans, 26, 43007 Tarragona, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3508-3462","authenticated-orcid":false,"given":"Juan","family":"Casanova-Ch\u00e1fer","sequence":"additional","affiliation":[{"name":"Microsystems Nanotechnologies for Chemical Analysis (MINOS), Universitat Rovira i Virgili, Avda. Pa\u00efsos Catalans, 26, 43007 Tarragona, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Frank","family":"G\u00fcell","sequence":"additional","affiliation":[{"name":"Microsystems Nanotechnologies for Chemical Analysis (MINOS), Universitat Rovira i Virgili, Avda. Pa\u00efsos Catalans, 26, 43007 Tarragona, Spain"},{"name":"ENFOCAT-IN2UB, Universitat de Barcelona, C\/Mart\u00ed i Franqu\u00e8s 1, 08028 Barcelona, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0869-468X","authenticated-orcid":false,"given":"Elisa","family":"Pe\u00f1a-Mart\u00edn","sequence":"additional","affiliation":[{"name":"Gnanomat S.L. C\/Faraday, 7. Parque Cient\u00edfico de Madrid, 28049 Madrid, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Sara","family":"Ruiz-Mart\u00ednez-Alcocer","sequence":"additional","affiliation":[{"name":"Gnanomat S.L. C\/Faraday, 7. Parque Cient\u00edfico de Madrid, 28049 Madrid, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Santiago","family":"de Bernardi-Mart\u00edn","sequence":"additional","affiliation":[{"name":"Gnanomat S.L. C\/Faraday, 7. Parque Cient\u00edfico de Madrid, 28049 Madrid, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1161-2363","authenticated-orcid":false,"given":"Alejandra","family":"Garc\u00eda-G\u00f3mez","sequence":"additional","affiliation":[{"name":"Gnanomat S.L. C\/Faraday, 7. Parque Cient\u00edfico de Madrid, 28049 Madrid, 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":"Microsystems Nanotechnologies for Chemical Analysis (MINOS), 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":"Microsystems Nanotechnologies for Chemical Analysis (MINOS), Universitat Rovira i Virgili, Avda. Pa\u00efsos Catalans, 26, 43007 Tarragona, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2023,6,30]]},"reference":[{"key":"ref_1","unstructured":"World Health Organization (2014, March 25). 7 Million Premature Deaths Annually Linked to Air Pollution. Available online: https:\/\/www.who.int\/health-topics\/air-pollution#tab=tab_2."},{"key":"ref_2","unstructured":"(2021, December 07). Air Quality in Europe. Available online: www.eea.europa.eu\/\/publications\/air-quality-in-europe-2021."},{"key":"ref_3","unstructured":"World Health Organization (2021). 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