{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,13]],"date-time":"2026-03-13T15:24:10Z","timestamp":1773415450367,"version":"3.50.1"},"reference-count":33,"publisher":"MDPI AG","issue":"8","license":[{"start":{"date-parts":[[2023,8,8]],"date-time":"2023-08-08T00:00:00Z","timestamp":1691452800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Romanian National Authority for Scientific Research and Innovation, UEFISCDI","award":["PN-III-P2-2.1-PTE-2021-0592"],"award-info":[{"award-number":["PN-III-P2-2.1-PTE-2021-0592"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Gels"],"abstract":"<jats:p>This article presents a layered mixed oxide thin film composed of Sn, Ti, Zn, and Pr obtained by sol\u2013gel deposition for gas sensing applications. The film was characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), Raman spectroscopy, UV-Vis spectroscopy, Scanning electron microscopy with energy dispersive X-ray spectroscopy (SEM-EDX), and Electrochemical impedance spectroscopy (EIS). X-ray diffraction results showed the presence of a single crystalline phase with a cassiterite-like structure. Raman spectroscopy revealed characteristic bands of oxygen-deficient SnO2-based nanocrystallites. The band gap energy calculated from UV-Vis spectroscopy is Eg = 3.83 eV. The XPS proved the presence on the surface of all elements introduced by the inorganic precursors as well as their oxidation states. Thus, Sn4+, Ti4+, Zn2+, and Pr3+ were detected on the surface. Moreover, by XPS, we highlighted the presence of OH groups and water adsorbed on the surface. SEM showed the five-layer morphology of the film after five successive depositions. Electrochemical properties were determined by EIS-impedance spectroscopy. The selectivity for gas sensing was also investigated for methane, propane, and formaldehyde and the gas sensing mechanism was explained. The results indicated that the mixed oxide thin film exhibited high sensitivity and selectivity towards specific gases.<\/jats:p>","DOI":"10.3390\/gels9080638","type":"journal-article","created":{"date-parts":[[2023,8,8]],"date-time":"2023-08-08T12:45:53Z","timestamp":1691498753000},"page":"638","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":3,"title":["Layered Sol\u2013Gel Deposition of a Sn, Ti, Zn, and Pr Mixed Oxide Thin Film with Electrical Properties for Gas Sensing"],"prefix":"10.3390","volume":"9","author":[{"given":"Izabella","family":"Dascalu","sequence":"first","affiliation":[{"name":"\u201cIlie Murgulescu\u201d Institute of Physical Chemistry\u2014Romanian Academy, Splaiul Independentei 202, 060021 Bucharest, Romania"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1327-7602","authenticated-orcid":false,"given":"Cristian","family":"Hornoiu","sequence":"additional","affiliation":[{"name":"\u201cIlie Murgulescu\u201d Institute of Physical Chemistry\u2014Romanian Academy, Splaiul Independentei 202, 060021 Bucharest, Romania"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jose Maria","family":"Calderon Moreno","sequence":"additional","affiliation":[{"name":"\u201cIlie Murgulescu\u201d Institute of Physical Chemistry\u2014Romanian Academy, Splaiul Independentei 202, 060021 Bucharest, Romania"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Petre","family":"Osiceanu","sequence":"additional","affiliation":[{"name":"\u201cIlie Murgulescu\u201d Institute of Physical Chemistry\u2014Romanian Academy, Splaiul Independentei 202, 060021 Bucharest, Romania"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Simona","family":"Somacescu","sequence":"additional","affiliation":[{"name":"\u201cIlie Murgulescu\u201d Institute of Physical Chemistry\u2014Romanian Academy, Splaiul Independentei 202, 060021 Bucharest, Romania"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2023,8,8]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"14992","DOI":"10.1016\/j.ceramint.2016.06.146","article-title":"Structural, Textural, Surface Chemistry and Sensing Properties of Mesoporous Pr, Zn Modified SnO2\u2013TiO2 Powder Composites","volume":"42","author":"Dascalu","year":"2016","journal-title":"Ceram. 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