The Investigation of a SAW Oxygen Gas Sensor Operated at Room Temperature, Based on Nanostructured ZnxFeyO Films

In this paper, we report a wireless gas sensor based on surface acoustic waves (SAW). For room temperature detection of oxygen gas, a novel nanostructured ZnxFeyO gas-sensitive film was deposited on the surface of a SAW resonator by an oblique magnetron co-sputtering method. The measurements of X-ray diffraction (XRD) and a scanning electron microscope (SEM) showed that the crystal phase composition and the microstructures of ZnxFeyO films were significantly affected by the content of Fe. The experimental results showed that the sensors had a good response to O2 at room temperature. The max frequency shift of the sensors reached 258 kHz as the O2 partial pressure was 20%. Moreover, X-ray photoelectron spectroscopy (XPS) was performed to analyze the role of Fe in the sensitization process of the ZnxFeyO film. In addition, the internal relationship between the Fe content of the film and the sensitivity of the sensor was presented and discussed. The research indicates that the nanostructured ZnxFeyO film has a good potential for room temperature O2 gas detection applications.

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A Highly Sensitive Room Temperature CO2 Gas Sensor Based on SnO2-rGO Hybrid Composite

Materials ◽

10.3390/ma14030522 ◽

2021 ◽

Vol 14 (3) ◽

pp. 522

Author(s):

Zhi Yan Lee ◽

Huzein Fahmi bin Hawari ◽

Gunawan Witjaksono bin Djaswadi ◽

Kamarulzaman Kamarudin

Keyword(s):

Electron Microscopy ◽

Carbon Dioxide ◽

Gas Sensor ◽

Photoelectron Spectroscopy ◽

Hybrid Composite ◽

Room Temperature ◽

Co2 Gas ◽

X Ray ◽

Wide Range ◽

Co2 Gas Sensor

A tin oxide (SnO2) and reduced graphene oxide (rGO) hybrid composite gas sensor for high-performance carbon dioxide (CO2) gas detection at room temperature was studied. Since it can be used independently from a heater, it emerges as a promising candidate for reducing the complexity of device circuitry, packaging size, and fabrication cost; furthermore, it favors integration into portable devices with a low energy density battery. In this study, SnO2-rGO was prepared via an in-situ chemical reduction route. Dedicated material characterization techniques including field emission scanning electron microscopy (FESEM), high-resolution transmission electron microscopy (HRTEM), energy dispersive X-ray (EDX) spectroscopy, Raman spectroscopy, and X-ray photoelectron spectroscopy (XPS) were conducted. The gas sensor based on the synthesized hybrid composite was successfully tested over a wide range of carbon dioxide concentrations where it exhibited excellent response magnitudes, good linearity, and low detection limit. The synergistic effect can explain the obtained hybrid gas sensor’s prominent sensing properties between SnO2 and rGO that provide excellent charge transport capability and an abundance of sensing sites.

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Template-free fabrication of NiO nanobelts: promising candidate for ethanol gas sensor at room temperature

Microelectronics International ◽

10.1108/mi-05-2015-0045 ◽

2016 ◽

Vol 33 (2) ◽

pp. 68-72 ◽

Cited By ~ 3

Author(s):

Zhiwei Li

Keyword(s):

Electron Microscopy ◽

Gas Sensor ◽

Photoelectron Spectroscopy ◽

Room Temperature ◽

Hydrothermal Reaction ◽

Ethanol Vapor ◽

Promising Candidate ◽

Content Type ◽

X Ray ◽

Template Free

Purpose The purpose of this paper is to seek a surfactant or template-free, simple and green method to fabricate NiO nanobelts and to find an effective technique to detect the ethanol vapor at room temperature. Design/methodology/approach NiO nanobelts with high aspect ratio and dispersive distribution have been synthesized by a template-free hydrothermal reaction at 160°C for 12 h. The products are studied by X-ray diffraction (XRD), energy dispersive spectroscopY, scanning electron microscopy, atomic force microscopy, high-resolution transmission electron microscopy, selective area electron diffractio and X-ray photoelectron spectroscopy. In particular, the room-temperature ethanol sensitivity of NiO nanobelts is investigated by the surface photo voltage (SPV) technique. Findings The prepared NiO nanobelts is single crystalline bunsenite structure with the length of approximately 10 μm and the diameter of approximately 30 nm. The atomic ratio of “Ni” to “O” is 0.92:1. When the concentration of ethanol vapor reaches 100 ppm, the sensitivity of NiO nanobelts is 7, which can meet the commercial demanding of ethanol gas sensor. Originality/value The NiO nanobelts can be obtained by a template-free, simple and green hydrothermal reaction at 160°C for 12 h. The NiO nanobelts-based gas sensor is a promising candidate for the application in ethanol monitoring at room temperature by SPV technique.

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Synthesis of Magnetic Ferrocene-Containing Polymer with Photothermal Effects for Rapid Degradation of Methylene Blue

Polymers ◽

10.3390/polym13040558 ◽

2021 ◽

Vol 13 (4) ◽

pp. 558

Author(s):

Wenhui Zhu ◽

Caiyun Zhang ◽

Yali Chen ◽

Qiliang Deng

Keyword(s):

Methylene Blue ◽

Photoelectron Spectroscopy ◽

Room Temperature ◽

Degradation Rate ◽

Model Compound ◽

Vibrating Sample Magnetometer ◽

Simulated Sunlight ◽

X Ray Diffraction ◽

X Ray ◽

Ft Ir

Photothermal materials are attracting more and more attention. In this research, we synthesized a ferrocene-containing polymer with magnetism and photothermal properties. The resulting polymer was characterized by Fourier-transform infrared (FT-IR), vibrating sample magnetometer (VSM), scanning electron microscope (SEM), energy dispersive X-ray spectroscopy (EDS), X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), and thermogravimetric analysis (TGA). Its photo-thermocatalytic activity was investigated by choosing methylene blue (MB) as a model compound. The degradation percent of MB under an irradiated 808 nm laser reaches 99.5% within 15 min, and the degradation rate is 0.5517 min−1, which is 145 times more than that of room temperature degradation. Under irradiation with simulated sunlight, the degradation rate is 0.0092 min−1, which is approximately 2.5 times more than that of room temperature degradation. The present study may open up a feasible route to degrade organic pollutants.

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Adsorption of oxygen at room temperature on polycrystalline titanium studied by ultraviolet and X-ray photoelectron spectroscopy

physica status solidi (b) ◽

10.1002/pssb.2220830107 ◽

1977 ◽

Vol 83 (1) ◽

pp. 77-84 ◽

Cited By ~ 18

Author(s):

A. L. Hagsteöm ◽

A. Platau ◽

S.-E. Kaelsson

Keyword(s):

Photoelectron Spectroscopy ◽

Room Temperature ◽

X Ray

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X-ray analysis of surface and pseudo-surface acoustic waves propagation in disordered La3Ga5SiO14 and ordered Ca3TaGa3Si2O14 crystals

2014 European Frequency and Time Forum (EFTF) ◽

10.1109/eftf.2014.7331428 ◽

2014 ◽

Author(s):

Olga Plotitcyna ◽

Dmitry Roshchupkin ◽

Dmitry Irzhak ◽

Evgenii Emelin ◽

Luc Ortega

Keyword(s):

Acoustic Waves ◽

Surface Acoustic Waves ◽

X Ray ◽

Waves Propagation

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ROOM TEMPERATURE PHOTOLUMINESCENCE OF POLYCRYSTALLINE SIC PREPARED FROM CARBON-SATURATED SI MELT

International Journal of Modern Physics B ◽

10.1142/s021797920201083x ◽

2002 ◽

Vol 16 (06n07) ◽

pp. 1047-1051

Author(s):

JIANPING MA ◽

ZHIMING CHEN ◽

GANG LU ◽

MINGBIN YU ◽

LIANMAO HANG ◽

...

Keyword(s):

Electron Microscopy ◽

Photoelectron Spectroscopy ◽

Room Temperature ◽

Uv Light ◽

X Ray Diffraction ◽

X Ray ◽

Room Temperature Photoluminescence ◽

Composition And Structure ◽

Light Excitation ◽

Scanning Electron

Intense photoluminescence (PL) has been observed at room temperature from the polycrystalline SiC samples prepared from carbon-saturated Si melt at a temperature ranging from 1500 to 1650°C. Composition and structure of the samples have been confirmed by means of X-ray photoelectron spectroscopy, X-ray diffraction and scanning electron microscopy. PL measurements with 325 nm UV light excitation revealed that the room temperature PL spectrum of the samples consists of 3 luminescent bands, the peak energies of which are 2.38 eV, 2.77 eV and 3.06 eV, respectively. The 2.38 eV band is much stronger than the others. It is suggested that some extrinsic PL mechanisms associated with defect or interface states would be responsible to the intensive PL observed at room temperature.

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