Chemically synthesized PbS Nano particulate thin films for a rapid NO2 gas sensor

AbstractRapid NO2 gas sensor has been developed based on PbS nanoparticulate thin films synthesized by Successive Ionic Layer Adsorption and Reaction (SILAR) method at different precursor concentrations. The structural and morphological properties were investigated by means of X-ray diffraction and field emission scanning electron microscope. NO2 gas sensing properties of PbS thin films deposited at different concentrations were tested. PbS film with 0.25 M precursor concentration showed the highest sensitivity. In order to optimize the operating temperature, the sensitivity of the sensor to 50 ppm NO2 gas was measured at different operating temperatures, from 50 to 200 °C. The gas sensitivity increased with an increase in operating temperature and achieved the maximum value at 150 °C, followed by a decrease in sensitivity with further increase of the operating temperature. The sensitivity was about 35 % for 50 ppm NO2 at 150 °C with rapid response time of 6 s. T90 and T10 recovery time was 97 s at this gas concentration.

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Polyaniline/SnO2 Nanocomposite Sensor for NO2 Gas Sensing at Low Operating Temperature

International Journal of Nanoscience ◽

10.1142/s0219581x15500118 ◽

2015 ◽

Vol 14 (04) ◽

pp. 1550011 ◽

Cited By ~ 8

Author(s):

A. Sharma ◽

M. Tomar ◽

V. Gupta ◽

A. Badola ◽

N. Goswami

Keyword(s):

Thin Films ◽

Gas Sensing ◽

High Sensitivity ◽

Morphological Properties ◽

X Ray Diffraction ◽

Chemical Route ◽

Sensing Properties ◽

Response Recovery ◽

Transmission Electron ◽

Gas Sensing Properties

In this paper gas sensing properties of 0.5–3% polyaniline (PAni) doped SnO 2 thin films sensors prepared by chemical route have been studied towards the trace level detection of NO 2 gas. The structural, optical and surface morphological properties of the PAni doped SnO 2 thin films were investigated by performing X-ray diffraction (XRD), Transmission electron microscopy (TEM) and Raman spectroscopy measurements. A good correlation has been identified between the microstructural and gas sensing properties of these prepared sensors. Out of these films, 1% PAni doped SnO 2 sensor showed high sensitivity towards NO 2 gas along with a sensitivity of 3.01 × 102 at 40°C for 10 ppm of gas. On exposure to NO 2 gas, resistance of all sensors increased to a large extent, even greater than three orders of magnitude. These changes in resistance upon removal of NO 2 gas are found to be reversible in nature and the prepared composite film sensors showed good sensitivity with relatively faster response/recovery speeds.

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Utilization and Measurements of Ferric Oxide thin films as a Nitride Dioxide gas sensor

journal of the college of basic education ◽

10.35950/cbej.v25i103.4543 ◽

2019 ◽

Vol 25 (103) ◽

pp. 11-22

Author(s):

Baha'a A.M. Al-Hilli ◽

Nabeel M.Merza

Keyword(s):

Thin Films ◽

Grain Size ◽

Ferric Oxide ◽

Gas Sensing ◽

Operating Temperature ◽

Gas Sensitivity ◽

Dc Sputtering ◽

Gas Sensing Properties ◽

Dc Sputtering Technique ◽

Sensitivity Increase

In this work, we investigate and revealed a (NO2) gas sensing properties of Ferric oxide (Fe2O3) thin films prepared using magnetron DC- sputtering technique, using different thicknesses concurring various deposition times. Each film tested with different sample temperature (200, 250 and 300) oC in order to enhance gas sensitivity. The results reveal that the sensitivity increase as the film thickness decrease (lower grain size) the film gas sensitivity increases, and the gas sensitivity increase also with increasing the operating temperature.

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Chemical synthesis and study of structural and optoelectronic properties of CdS thin films: Effect of SILAR growth cycles

JOURNAL OF ADVANCES IN PHYSICS ◽

10.24297/jap.v9i3.1351 ◽

2015 ◽

Vol 9 (3) ◽

pp. 2461-2469

Author(s):

S. R. Gosavi ◽

K. B. Chaudhari

Keyword(s):

Thin Films ◽

Average Crystallite Size ◽

X Ray Diffraction ◽

Silar Method ◽

Growth Cycles ◽

Glass Substrates ◽

Layer Adsorption ◽

Cds Thin Films ◽

Structural And Optoelectronic Properties ◽

Deposited Film

CdS thin films were deposited on glass substrates by using successive ionic layer adsorption and reaction (SILAR) method at room temperature. The effect of SILAR growth cycles on structural, morphological, optical and electrical properties of the films has been studied.Â The thickness of the deposited film is measured by employing weight difference method. The X-ray diffraction (XRD) and field emission scanning electron microscopy (FE-SEM) studies showed that all the films exhibit polycrystalline nature and are covered well with glass substrates. The values of average crystallite size were found to be 53 nm, 58 nm, 63 nm and 71 nm corresponding to the thin films deposited with 30, 40, 50 and 60 SILAR growth cycles respectively. From the UVâ€“VIS spectra of the deposited thin films, it was seen that both the absorption properties and energy bandgap of the films changes with increasing number of SILAR growth cycles. A decrease of electrical resistivity has been observed with increasing SILAR growth cycle.Â

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Structural, morphological and gas sensing properties of Zn1−xSnxO thin films by SILAR method

Applied Physics A ◽

10.1007/s00339-021-04354-7 ◽

2021 ◽

Vol 127 (4) ◽

Author(s):

Irmak Karaduman Er ◽

Memet Ali Yıldırım ◽

H. Hasan Örkçü ◽

Aytunç Ateş ◽

Selim Acar

Keyword(s):

Thin Films ◽

Gas Sensing ◽

Silar Method ◽

Sensing Properties ◽

Gas Sensing Properties

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A Novel Tungsten Trioxide Based Gas Sensor for Indoor Formaldehyde Detection

Journal of Nanoelectronics and Optoelectronics ◽

10.1166/jno.2021.2936 ◽

2021 ◽

Vol 16 (3) ◽

pp. 363-367

Author(s):

Gaoqi Zhang ◽

Fan Zhang ◽

Kaifang Wang ◽

Tao Tian ◽

Shanyu Liu ◽

...

Keyword(s):

Electron Microscope ◽

Gas Sensor ◽

Indoor Air ◽

Gas Sensing ◽

X Ray Diffraction ◽

X Ray ◽

Sensing Material ◽

Transmission Electron ◽

Gas Sensing Properties ◽

Gas Response

Accurate and real-time detection of formaldehyde (HCHO) in indoor air is urgently needed for human health. In this work, a ceramic material (WO3·H2O) with unique structure was successfully prepared using an efficient hydrothermal method. The crystallinity, morphology and microstructure of the as-prepared sensing material were analyzed by X-ray diffraction (XRD), field emission scanning electron microscope (FESEM) as well as transmission electron microscope (TEM). The characterization results suggest that the as-prepared sample is composed of square-like nanoplates with uneven surface. Formaldehyde vapor is utilized as the target gas to investigate gas sensing properties of the synthesized novel nanoplates. The testing results indicate that the as-fabricated gas sensor exhibit high gas response and excellent repeatability to HCHO gas. The response value (Ra/Rg) is 24.5 towards 70 ppm HCHO gas at 350 °C. Besides, the gas sensing mechanism was described.

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Preparation of Cu2ZnSnS4 Thin Films by Successive Ionic Layer Adsorption and Reaction (SILAR) Method for Supercapacitor Applications

Journal of Nanoscience and Nanotechnology ◽

10.1166/jnn.2020.17888 ◽

2020 ◽

Vol 20 (10) ◽

pp. 6235-6244 ◽

Cited By ~ 3

Author(s):

A. Murugan ◽

V. Siva ◽

A. Shameem ◽

S. Asath Bahadur

Keyword(s):

Thin Films ◽

Electrochemical Behavior ◽

Electrochemical Impedance ◽

X Ray Diffraction ◽

Silar Method ◽

Layer Adsorption ◽

Diffraction Patterns ◽

Czts Thin Films ◽

Supercapacitor Applications ◽

Ionic Layer

The Cu2ZnSnS4 (CZTS) thin films have been prepared at different deposition cycles, deposited on a glass substrate by successive ionic layer adsorption and reaction (SILAR) method followed by the annealing process at elevated temperature. The investigations on the films have been carried out to understand and confirm its structure, functional group present, crystalline morphology, optical and electrochemical behavior. The powder X-ray diffraction patterns recorded indicate that the deposited films are formed in the tetragonal structure. Other parameters like grain size, dislocation density, and microstrain are also calculated. The uniform surface of the films with spherical shaped morphology has been observed by Scanning Electron Microscopy, and the elemental compositions have been confirmed by EDAX. Electrochemical behavior such as cyclic voltammetry, electrochemical impedance spectroscopy and galvanostatic charge–discharge analysis have been carried out by electrochemical workstation. The modified electrode exhibits maximum specific capacitance value as 416 F/g for a pure sample. Optical studies have shown that the band gaps are estimated between 1.40 eV and 1.57 eV.

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Influence of Ni doping on the nitric oxide gas sensing properties of Zn1−xNixO thin films synthesized by silar method

Materials Research Express ◽

10.1088/2053-1591/ab1dce ◽

2019 ◽

Vol 6 (8) ◽

pp. 086419 ◽

Cited By ~ 2

Author(s):

B Soltabayev ◽

I Karaduman Er ◽

H Surel ◽

A Coşkun ◽

M A Yıldırım ◽

...

Keyword(s):

Nitric Oxide ◽

Thin Films ◽

Gas Sensing ◽

Ni Doping ◽

Silar Method ◽

Sensing Properties ◽

Gas Sensing Properties

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Gas-sensing features of nanostructured tellurium thin films

Beilstein Journal of Nanotechnology ◽

10.3762/bjnano.11.85 ◽

2020 ◽

Vol 11 ◽

pp. 1010-1018

Author(s):

Dumitru Tsiulyanu

Keyword(s):

Thin Films ◽

Gas Sensing ◽

Operating Temperature ◽

Active Surface ◽

Active Surface Area ◽

Gas Sensitivity ◽

Nanocrystalline And Amorphous ◽

Recovery Times ◽

Order Of Magnitude ◽

Response And Recovery

Nanocrystalline and amorphous nanostructured tellurium (Te) thin films were grown and their gas-sensing properties were investigated at different operating temperatures with respect to scanning electron microscopy and X-ray diffraction analyses. It was shown that both types of films interacted with nitrogen dioxide, which resulted in a decrease of electrical conductivity. The gas sensitivity, as well as the response and recovery times, differed between these two nanostructured films. It is worth mentioning that these properties also depend on the operating temperature and the applied gas concentration on the films. An increase in the operating temperature decreased not only the response and recovery times but also the gas sensitivity of the nanocrystalline films. This shortcoming could be solved by using the amorphous nanostructured Te films which, even at 22 °C, exhibited higher gas sensitivity and shorter response and recovery times by more than one order of magnitude in comparison to the nanocrystalline Te films. These results were interpreted in terms of an increase in disorder (amorphization), leading to an increase in the surface chemical activity of chalcogenides, as well as an increase in the active surface area due to substrate porosity.

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V2O5 Thin Films as Nitrogen Dioxide Sensors

Proceedings ◽

10.3390/proceedings2130759 ◽

2018 ◽

Vol 2 (13) ◽

pp. 759

Author(s):

Krystyna Schneider ◽

Wojciech Maziarz

Keyword(s):

Thin Films ◽

Nitrogen Dioxide ◽

Gas Sensing ◽

Optical Transmittance ◽

Fused Silica ◽

X Ray Diffraction ◽

Gas Sensing Properties ◽

Oxygen Gas ◽

V2o5 Thin Films ◽

Phase Characterization

V2O5 thin films were deposited onto insulating support (either fused silica or alumina) by means of rf reactive sputtering from a metallic vanadium target. Argon-oxygen gas mixtures of different compositions controlled by the flow rates were used for sputtering. X-ray diffraction at glancing incidence (GIXD) and Scanning Electronic Microscopy (SEM) were used for structural and phase characterization. Optical transmittance and reflectance spectra were recorded with a Lambda 19 Perkin-Elmer double spectrophotometer. Thickness of the films was determined from the profilometry. It has been confirmed by GIXD that the deposited films are composed of V2O5 phase. The estimated optical band gap was ca. 2.5 eV. The gas sensing properties of V2O5 thin films were investigated at RT-690 K towards NO2 gas of 0–20 ppm. The results indicated that material exhibited good response and reversibility towards nitrogen dioxide.

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