{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,16]],"date-time":"2026-06-16T10:48:59Z","timestamp":1781606939940,"version":"3.54.5"},"reference-count":49,"publisher":"MDPI AG","issue":"10","license":[{"start":{"date-parts":[[2023,5,10]],"date-time":"2023-05-10T00:00:00Z","timestamp":1683676800000},"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":["H2020-MSCA-RISE-2018-823895"],"award-info":[{"award-number":["H2020-MSCA-RISE-2018-823895"]}]},{"name":"Marie Sk\u0142odowska-Curie Actions (MSCA) Research and Innovation Staff Exchange (RISE)","award":["TED2021-131442B-C31"],"award-info":[{"award-number":["TED2021-131442B-C31"]}]},{"name":"Marie Sk\u0142odowska-Curie Actions (MSCA) Research and Innovation Staff Exchange (RISE)","award":["2021 SGR 147"],"award-info":[{"award-number":["2021 SGR 147"]}]},{"name":"MICINN","award":["H2020-MSCA-RISE-2018-823895"],"award-info":[{"award-number":["H2020-MSCA-RISE-2018-823895"]}]},{"name":"MICINN","award":["TED2021-131442B-C31"],"award-info":[{"award-number":["TED2021-131442B-C31"]}]},{"name":"MICINN","award":["2021 SGR 147"],"award-info":[{"award-number":["2021 SGR 147"]}]},{"name":"AGAUR","award":["H2020-MSCA-RISE-2018-823895"],"award-info":[{"award-number":["H2020-MSCA-RISE-2018-823895"]}]},{"name":"AGAUR","award":["TED2021-131442B-C31"],"award-info":[{"award-number":["TED2021-131442B-C31"]}]},{"name":"AGAUR","award":["2021 SGR 147"],"award-info":[{"award-number":["2021 SGR 147"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Nanostructured tungsten disulfide (WS2) is one of the most promising candidates for being used as active nanomaterial in chemiresistive gas sensors, as it responds to hydrogen gas at room temperature. This study analyzes the hydrogen sensing mechanism of a nanostructured WS2 layer using near-ambient-pressure X-ray photoelectron spectroscopy (NAP-XPS) and density functional theory (DFT). The W 4f and S 2p NAP-XPS spectra suggest that hydrogen makes physisorption on the WS2 active surface at room temperature and chemisorption on tungsten atoms at temperatures above 150 \u00b0C. DFT calculations show that a hydrogen molecule physically adsorbs on the defect-free WS2 monolayer, while it splits and makes chemical bonds with the nearest tungsten atoms on the sulfur point defect. The hydrogen adsorption on the sulfur defect causes a large charge transfer from the WS2 monolayer to the adsorbed hydrogen. In addition, it decreases the intensity of the in-gap state, which is generated by the sulfur point defect. Furthermore, the calculations explain the increase in the resistance of the gas sensor when hydrogen interacts with the WS2 active layer.<\/jats:p>","DOI":"10.3390\/s23104623","type":"journal-article","created":{"date-parts":[[2023,5,11]],"date-time":"2023-05-11T01:37:24Z","timestamp":1683769044000},"page":"4623","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":32,"title":["Hydrogen Sensing Mechanism of WS2 Gas Sensors Analyzed with DFT and NAP-XPS"],"prefix":"10.3390","volume":"23","author":[{"given":"Tomoya","family":"Minezaki","sequence":"first","affiliation":[{"name":"Department of Materials Science, Graduate School of Science and Engineering, Chiba University, 1-33 Yayoi-cho, Inage-ku, Chiba-shi 263-8522, Chiba, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1247-9886","authenticated-orcid":false,"given":"Peter","family":"Kr\u00fcger","sequence":"additional","affiliation":[{"name":"Department of Materials Science, Graduate School of Science and Engineering, Chiba University, 1-33 Yayoi-cho, Inage-ku, Chiba-shi 263-8522, Chiba, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1533-6482","authenticated-orcid":false,"given":"Fatima Ezahra","family":"Annanouch","sequence":"additional","affiliation":[{"name":"Departament d\u2019Enginyeria Electronica, Universitat Rovira i Virgili, Pa\u00efsos Catalans 26, 43007 Tarragona, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3508-3462","authenticated-orcid":false,"given":"Juan","family":"Casanova-Ch\u00e1fer","sequence":"additional","affiliation":[{"name":"Chimie des Interactions Plasma Surface, CIRMAP, Universit\u00e9 de Mons, Place du Parc 23, 7000 Mons, Belgium"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Aanchal","family":"Alagh","sequence":"additional","affiliation":[{"name":"Departament d\u2019Enginyeria Electronica, Universitat Rovira i Virgili, Pa\u00efsos Catalans 26, 43007 Tarragona, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ignacio J.","family":"Villar-Garcia","sequence":"additional","affiliation":[{"name":"ALBA Synchrotron Light Source, Carrer de la Llum 2-26, 08290 Cerdanyola del Vall\u00e8s, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Virginia","family":"P\u00e9rez-Dieste","sequence":"additional","affiliation":[{"name":"ALBA Synchrotron Light Source, Carrer de la Llum 2-26, 08290 Cerdanyola del Vall\u00e8s, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6164-4342","authenticated-orcid":false,"given":"Eduard","family":"Llobet","sequence":"additional","affiliation":[{"name":"Departament d\u2019Enginyeria Electronica, Universitat Rovira i Virgili, Pa\u00efsos Catalans 26, 43007 Tarragona, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3330-6693","authenticated-orcid":false,"given":"Carla","family":"Bittencourt","sequence":"additional","affiliation":[{"name":"Chimie des Interactions Plasma Surface, CIRMAP, Universit\u00e9 de Mons, Place du Parc 23, 7000 Mons, Belgium"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2023,5,10]]},"reference":[{"key":"ref_1","unstructured":"(2023, April 06). 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