Investigation of gas sensing mechanism of SnO.sub.2./sub. based chemiresistor using near ambient pressure XPS

0496392 - FZÚ 2019 RIV NL eng J - Journal Article
Vorokhta, M. - Khalakhan, I. - Vondráček, Martin - Tomeček, D. - Vorokhta, Maryna - Marešová, E. - Nováková, A. - Vlček, J. - Fitl, P. - Novotný, Michal - Hozák, P. - Lančok, Ján - Vrňata, M. - Matolínová, I. - Matolín, V.
Investigation of gas sensing mechanism of SnO₂ based chemiresistor using near ambient pressure XPS.
Surface Science. Roč. 677, Nov (2018), s. 284-290. ISSN 0039-6028. E-ISSN 1879-2758
R&D Projects: GA ČR GA17-13427S
Institutional support: RVO:68378271 ; RVO:67985891
Keywords : near ambient pressure XPS * nanostructured tin oxide layer * gas sensing mechanism * ethanol vapors * chemisorbed oxygen
OECD category: Condensed matter physics (including formerly solid state physics, supercond.); Inorganic and nuclear chemistry (USMH-B)
Impact factor: 1.849, year: 2018

In this article, we present the results of an investigation into chemical processes which take place at the surface of SnO2-based chemiresistor in various atmospheres (1 mbar of argon, 1 mbar of oxygen, 0.1 mbar of ethanol,1 mbar of oxygen +0.1 mbar of ethanol mixture) at common working temperatures (450 and 573 K). The key method for nanoscale analysis was the Near Ambient Pressure X-ray Photoelectron Spectroscopy. In parallel the resistance and DC-responses of SnO2 layer were in-situ monitored providing information about macroscale processes during gas sensing. The change in the sensor resistance after exposure to the ethanol-containing atmospheres together with the disappearance of the band bending effect and observation of different carbonaceous groups including ethoxy groups and acetaldehyde molecules on the sensor surface in the XPS spectra supported the theory of chemical interaction of ethanol with the chemisorbed oxygen.
Permanent Link: http://hdl.handle.net/11104/0289190