Nanocomposites SnO2/SiO2:SiO2 Impact on the Active Centers and Conductivity Mechanism Full article
Journal |
Materials
ISSN: 1996-1944 |
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Output data | Year: 2019, Volume: 12, Number: 21, Article number : 3618, Pages count : 15 DOI: 10.3390/ma12213618 | ||||||||||
Tags | Active surface groups; Conductivity mechanism; Nanocomposites; Oxygen chemisorption; Paramagnetic centers; Silicon dioxide; Tin dioxide | ||||||||||
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Affiliations |
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Funding (1)
1 | Russian Science Foundation | 19-13-00245 (АААА-А19-119050790037-4) |
Abstract:
This paper is focused on the effect of the stabilizing component SiO2 on the type and concentration of active sites in SnO2/SiO2 nanocomposites compared with nanocrystalline SnO2. Previously, we found that SnO2/SiO2 nanocomposites show better sensor characteristics in CO detection (lower detection limit, higher sensor response, and shorter response time) compared to pure SnO2 in humid air conditions. Nanocomposites SnO2/SiO2 synthesized using the hydrothermal method were characterized by low temperature nitrogen adsorption, XRD, energy dispersive X-ray spectroscopy (EDX), thermo-programmed reduction with hydrogen (TPR-H2), IR-, and electron-paramagnetic resonance (EPR)-spectroscopy methods. The electrophysical properties of SnO2 and SnO2/SiO2 nanocomposites were studied depending on the oxygen partial pressure in the temperature range of 200-400 °C. The introduction of SiO2 results in an increase in the concentration of paramagnetic centers Sn3+ and the amount of surface hydroxyl groups and chemisorbed oxygen and leads to a decrease in the negative charge on chemisorbed oxygen species. The temperature dependences of the conductivity of SnO2 and SnO2/SiO2 nanocomposites are linearized in Mott coordinates, which may indicate the contribution of the hopping mechanism with a variable hopping distance over local states. © 2019 by the authors.
Cite:
Gulevich D.
, Rumyantseva M.
, Marikutsa A.
, Shatalova T.
, Konstantinova E.
, Gerasimov E.
, Gaskov A.
Nanocomposites SnO2/SiO2:SiO2 Impact on the Active Centers and Conductivity Mechanism
Materials. 2019. V.12. N21. 3618 :1-15. DOI: 10.3390/ma12213618 WOS Scopus РИНЦ
Nanocomposites SnO2/SiO2:SiO2 Impact on the Active Centers and Conductivity Mechanism
Materials. 2019. V.12. N21. 3618 :1-15. DOI: 10.3390/ma12213618 WOS Scopus РИНЦ
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Full text from publisher
Dates:
Submitted: | Oct 2, 2019 |
Accepted: | Nov 1, 2019 |
Published print: | Nov 1, 2019 |
Published online: | Nov 4, 2019 |
Identifiers:
Web of science | WOS:000502798800159 |
Scopus | 2-s2.0-85074636075 |
Elibrary | 41265805 |
Chemical Abstracts | 2020:816018 |
PMID | 31689938 |
OpenAlex | W2984963910 |