Electron Microscopy of TiO2-based Thick Films for Gas Sensors

Preparation and some of the chemical and microstructural aspects of thick films of the YBa 2 Cu 3 O 7−x superconductors (herein designated as YBaCuO) using precalcined YBaCuO powders and a colloidal method are described. Films on alumina substrates were made from calcined YBaCuO powders dispersed in hexane using a commerical dispersant which acts as a steric stabilizer and binder. The additive decomposes without residues at relatively low temperatures, and structurally stable and uniform films are obtained for proper dosage of the dispersant. Scanning electron microscopy has been used to examine the microstructure, quality and sinterability of the films. An example of the use of other additives to improve sintering and adhesion of the film to the substrate is also described. Substrate/film interaction has been studied by compositional mapping using an electron probe microanalyzer. The results show a substantial reaction layer (1−2μm) of barium aluminate and a significant diffusion distance (of several microns) of aluminum into the film.

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Spinel MgFe2O4 thick films: A colloidal approach for developing gas sensors

Materials Letters ◽

10.1016/j.matlet.2017.11.009 ◽

2018 ◽

Vol 213 ◽

pp. 27-30 ◽

Cited By ~ 26

Author(s):

Jayvant Patil ◽

Digambar Nadargi ◽

Imtiaz S. Mulla ◽

S.S. Suryavanshi

Keyword(s):

Gas Sensors ◽

Thick Films

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Synthesis and Characterization of Nanostructured TiO2-SnO2 Composite

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.975.233 ◽

2014 ◽

Vol 975 ◽

pp. 233-237

Author(s):

Joelma C. S. Breve ◽

Dayse I. dos Santos

Keyword(s):

Electron Microscopy ◽

Heat Treatment ◽

Thermal Analysis ◽

Gas Sensors ◽

Catalytic Properties ◽

Rutile Phase ◽

Synthesis And Characterization ◽

Vis Spectroscopy ◽

Scanning Electron

Nanostructured composites based on titanium dioxide have been studied in order to improve optical and photo-catalytic properties, as well as their performance in gas sensors. In this work, titanium and tin dioxides were simultaneously synthesized by the polyol method resulting in TiO2 platelet coated with SnO2 nanoparticles as was observed by scanning electron microscopy. The thermal analysis showed that the combined synthesis promotes more easily the crystallization of the TiO2 rutile phase. The composite obtained after heat treatment at 500 °C showed to be formed of almost only rutile phases of both oxides. The optical properties analyzed by UV-Vis spectroscopy showed that the combined oxides have higher absorbance, which reinforces a model found in the literature based on the flow of photo-generated electrons to the conduction band of SnO2 delaying the recombination of charges.

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Получение пленки оксида железа на сапфировой подложке

Письма в журнал технической физики ◽

10.21883/pjtf.2018.12.46293.16989 ◽

2018 ◽

Vol 44 (12) ◽

pp. 68

Author(s):

Ю.В. Клунникова ◽

С.П. Малюков ◽

А.В. Саенко ◽

Д.А. Сарычев ◽

В.В. Китаев

Keyword(s):

Electron Microscopy ◽

Scanning Electron Microscopy ◽

Laser Radiation ◽

Gas Sensors ◽

X Ray ◽

Magnetic Devices ◽

Sapphire Substrates ◽

Transmission Mössbauer Spectroscopy ◽

Scanning Electron ◽

Superparamagnetic State

AbstractIron-oxide films on sapphire substrates were obtained using laser radiation with 1064-nm wavelength and studied by methods of scanning electron microscopy, energy-dispersive X-ray spectroscopy, and transmission Mössbauer spectroscopy. The obtained Fe_2O_3 films probably occur in a superparamagnetic state and may find application in gas sensors and various magnetic devices.

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SnO2 Substituted In2O3 Thick Films as PPM Level NH3 Gas Sensors

International Journal for Research in Applied Science and Engineering Technology ◽

10.22214/ijraset.2021.32812 ◽

2021 ◽

Vol 9 (1) ◽

pp. 346-351

Author(s):

S. M. Yenorkar

Keyword(s):

Gas Sensors ◽

Thick Films ◽

Ppm Level

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Structural Characterization of Nanocrystalline La1-xSrxCrO3 Thick Films for H2S Gas Sensors

Journal of Sensor Technology ◽

10.4236/jst.2012.21003 ◽

2012 ◽

Vol 02 (01) ◽

pp. 13-18 ◽

Cited By ~ 3

Author(s):

Ashish V. Kadu ◽

Archana B. Bodade ◽

Anjali B. Bodade ◽

G. N. Chaudhari

Keyword(s):

Gas Sensors ◽

Structural Characterization ◽

Thick Films

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Low Working Temperature of ZnO-MoS2 Nanocomposites for Delaying Aging with Good Acetylene Gas-Sensing Properties

Nanomaterials ◽

10.3390/nano10101902 ◽

2020 ◽

Vol 10 (10) ◽

pp. 1902

Author(s):

Sijie Wang ◽

Weigen Chen ◽

Jian Li ◽

Zihao Song ◽

He Zhang ◽

...

Keyword(s):

Electron Microscopy ◽

Gas Sensors ◽

Photoelectron Spectroscopy ◽

Gas Sensing ◽

Morphological Characteristics ◽

Molar Ratio ◽

X Ray ◽

Sensing Properties ◽

Working Temperature ◽

Current Concerns

The long-term stability and the extension of the use time of gas sensors are one of the current concerns. Lowering the working temperature is one of the most effective methods to delay aging. In this paper, pure MoS2 and ZnO-MoS2 nanocomposites were successfully prepared by the hydrothermal method, and the morphological characteristics were featured by scanning electron microscopy (SEM), X-ray diffraction (XRD), transmission electron microscopy (TEM) and X-ray photoelectron spectroscopy (XPS). Pure MoS2 and ZnO-MoS2 nanocomposites, as a comparison, were used to study the aging characteristic. The sensing properties of the fabricated gas sensors with an optimal molar ratio ZnO-MoS2 (Zn:Mo = 1:2) were recorded, and the results exhibit a high gas-sensing response and good repeatability to the acetylene detection. The working temperature was significantly lower than for pure MoS2. After aging for 40 days, all the gas-sensing response was relatively attenuated, and pure MoS2 exhibits a faster decay rate and lower gas-sensing response than nanocomposites. The better gas-sensing characteristic of nanocomposites after aging was possibly attributed to the active interaction between ZnO and MoS2.

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