Dokument: Oxygen Sensing of Pt/PEO-TiO2 in Humid Atmospheres at Moderate Temperatures
| Titel: | Oxygen Sensing of Pt/PEO-TiO2 in Humid Atmospheres at Moderate Temperatures | |||||||
| URL für Lesezeichen: | https://docserv.uni-duesseldorf.de/servlets/DocumentServlet?id=71400 | |||||||
| URN (NBN): | urn:nbn:de:hbz:061-20251117-114815-0 | |||||||
| Kollektion: | Publikationen | |||||||
| Sprache: | Englisch | |||||||
| Dokumententyp: | Wissenschaftliche Texte » Artikel, Aufsatz | |||||||
| Medientyp: | Text | |||||||
| Autoren: | Engelkamp, Bernd [Autor] Schierbaum, Klaus [Autor] | |||||||
| Dateien: |
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| Stichwörter: | plasma electrolytic oxidation , Pt/TiO₂ , ionosorption , oxygen gas sensor , titanium dioxide | |||||||
| Beschreibung: | Here, we show that the presence of adsorbed water improves the oxygen-sensing properties of Pt/TiO2at moderate temperatures. The studied interface is based on porous plasma electrolytic oxidized titanium (PEO-TiO2) covered with platinum clusters. The electrical resistance across Pt/PEO-TiO2 is explained by an electronic depletion layer. Oxygen adsorbates further increase the depletion by inducing extrinsic interface states, which are occupied by TiO2 conduction band electrons. The high oxygen partial pressure in ambient air substantially limits the electron transport across the interface. Our DC measurements at defined levels of humidity at 30 ∘C show that adsorbed water counteracts this shortcoming, allowing oxygen sensing at room conditions. In addition, response and recovery times from temporal oxygen exposure decrease with humidity. We attribute the effects to competing adsorption processes and reactions of water with adsorbed oxygen species and/or lattice oxygen, which involve electron re-injection to the TiO2 conduction band. Elevated temperatures up to 170 ∘C attenuate the effects, presumably due to the lower binding strength to the surface of molecular water compared with oxygen adsorbates. | |||||||
| Rechtliche Vermerke: | Originalveröffentlichung:
Engelkamp, B., & Schierbaum, K. (2021). Oxygen Sensing of Pt/PEO-TiO2 in Humid Atmospheres at Moderate Temperatures [OnlineRessource]. Sensors, 21(7), Article 2558. https://doi.org/10.3390/s21072558 | |||||||
| Lizenz: |  Dieses Werk ist lizenziert unter einer Creative Commons Namensnennung 4.0 International Lizenz | |||||||
| Fachbereich / Einrichtung: | Mathematisch- Naturwissenschaftliche Fakultät | |||||||
| Dokument erstellt am: | 17.11.2025 | |||||||
| Dateien geändert am: | 17.11.2025 |
