Gas sensitive ZnO structures with reduced humidity-interference

0509556 - ÚFM 2020 RIV CH eng J - Journal Article
Vallejos, S. - Gràcia, I. - Pizúrová, Naděžda - Figueras, E. - Čechal, J. - Hubálek, J. - Cané, C.
Gas sensitive ZnO structures with reduced humidity-interference.
Sensors and Actuators B - Chemical. Roč. 301, DEC (2019), č. článku 127054. E-ISSN 0925-4005
R&D Projects: GA MŠMT(CZ) EF16_013/0001823
Institutional support: RVO:68081723
Keywords : Gas sensor * Humidity * Nanostructures * Zinc oxide
OECD category: Condensed matter physics (including formerly solid state physics, supercond.)
Impact factor: 7.100, year: 2019
Method of publishing: Open access
https://doi.org/10.1016/j.snb.2019.127054

The Authors Gas microsensors based on zinc oxide structures with rod- and needle-like morphology, both integrated via a non-catalyzed vapor-solid mechanism enabled using aerosol-assisted chemical vapor deposition, are developed. Analyses of the films via SEM, TEM, XPS, and water contact angle indicate a higher concentration of oxygen vacancies, higher aspect ratio and higher roughness factor for the needles than for the rods. Gas sensing tests towards hydrogen and carbon monoxide demonstrate reduced humidity-interference, and higher responses to the analytes for the needle-based systems compared to the rods. These results are attributed to the morphology of the sensitive materials, which not only affects the surface-area-to-volume-ratio of the films but also their surface chemistry. These findings indicate that a thorough optimization of morphology, structure and surface properties of gas sensitive metal oxides could allow for more reliable sensor operation in humid conditions.
Permanent Link: http://hdl.handle.net/11104/0301464