• Rumyantseva, Marina
• Marikutsa, Artem
• Gaskov, Alexander
• Gerasimov, Evgeny
• Shatalova, Tatyana
• Khmelevsky, Nikolay
• Gulevich, Dayana
• Krivetskiy, Valeriy

Abstract

<jats:p>Nanocomposites SnO2/SiO2 with a silicon content of [Si]/([Sn] + [Si]) = 3/86 mol.% were obtained by the hydrothermal method. The composition and microstructure of the samples were characterized by EDX, XRD, HRTEM and single-point Brunauer-Emmet-Teller (BET) methods. The surface sites were investigated using thermal analysis, FTIR and XPS. It is shown that the insertion of silicon dioxide up to the value of [Si]/([Sn] + [Si]) = 19 mol.% stabilizes the growth of SnO2 nanoparticles during high-temperature annealing, which makes it possible to obtain sensor materials operating stably at different temperature conditions. The sensor properties of SnO2 and SnO2/SiO2 nanocomposites were studied by in situ conductivity measurements in the presence of 10–200 ppm CO in dry and humid air in the temperature range of 150–400 °C. It was found that SnO2/SiO2 nanocomposites are more sensitive to CO in humid air as compared to pure SnO2, and the sample with silicon content [Si]/([Sn] + [Si] = 13 mol.% is resistant to changes in relative air humidity (RH = 4%–65%) in the whole temperature range, which makes it a promising sensor material for detecting CO in real conditions. The results are discussed in terms of the changes in the composition of surface-active groups, which alters the reactivity of the obtained materials.</jats:p>

Topics

• nanoparticle
• nanocomposite
• impedance spectroscopy
• microstructure
• surface
• x-ray diffraction
• x-ray photoelectron spectroscopy
• thermal analysis
• Silicon
• annealing
• Energy-dispersive X-ray spectroscopy
• gas phase