Gas Sensing Properties of Perovskite Decorated Graphene at Room Temperature

This paper explores the gas sensing properties of graphene nanolayers decorated with lead halide perovskite (CH3NH3PbBr3) nanocrystals to detect toxic gases such as ammonia (NH3) and nitrogen dioxide (NO2). A chemical-sensitive semiconductor film based on graphene has been achieved, being decorated with CH3NH3PbBr3 perovskite (MAPbBr3) nanocrystals (NCs) synthesized, and characterized by several techniques, such as field emission scanning electron microscopy, transmission electron microscopy and X-ray photoelectron spectroscopy. Reversible responses were obtained towards NO2 and NH3 at room temperature, demonstrating an enhanced sensitivity when the graphene is decorated by MAPbBr3 NCs. Furthermore, the effect of ambient moisture was extensively studied, showing that the use of perovskite NCs in gas sensors can become a promising alternative to other gas sensitive materials, due to the protective character of graphene, resulting from its high hydrophobicity. Besides, a gas sensing mechanism is proposed to understand the effects of MAPbBr3 sensing properties.

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Preparation and NH3 Gas-Sensing Properties of Double-Shelled Hollow ZnTiO3 Microrods

Sensors ◽

10.3390/s20010046 ◽

2019 ◽

Vol 20 (1) ◽

pp. 46 ◽

Cited By ~ 1

Author(s):

Pi-Guey Su ◽

Xiang-Hong Liu

Keyword(s):

Electron Microscopy ◽

Room Temperature ◽

Gas Sensing ◽

Strong Response ◽

X Ray ◽

Sensing Properties ◽

Diallyldimethylammonium Chloride ◽

Transmission Electron ◽

Low Concentrations ◽

Gas Sensing Properties

A novel double-shelled hollow (DSH) structure of ZnTiO3 microrods was prepared by self-templating route with the assistance of poly(diallyldimethylammonium chloride) (PDDA) in an ethylene glycol (EG) solution, which was followed by calcining. Moreover, the NH3 gas-sensing properties of the DSH ZnTiO3 microrods were studied at room temperature. The morphology and composition of DSH ZnTiO3 microrods films were analyzed using scanning electron microscopy (SEM), transmission electron microscopy (TEM) and X-ray diffractometry (XRD). The formation process of double-shelled hollow microrods was discussed in detail. The comparative gas-sensing results revealed that the DSH ZnTiO3 microrods had a higher response to NH3 gas at room temperature than those of the TiO2 solid microrods and DSH ZnTiO3 microrods did in the dark. More importantly, the DSH ZnTiO3 microrods exhibited a strong response to low concentrations of NH3 gas at room temperature.

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Controlled Synthesis of Hierarchically Assembled Porous ZnO Microspheres with Enhanced Gas-Sensing Properties

Journal of Nanomaterials ◽

10.1155/2015/680306 ◽

2015 ◽

Vol 2015 ◽

pp. 1-9

Author(s):

Shengsheng You ◽

Haojie Song ◽

Jing Qian ◽

Ya-li Sun ◽

Xiao-hua Jia

Keyword(s):

Electron Microscopy ◽

Gas Sensing ◽

Hexagonal Phase ◽

Trisodium Citrate ◽

Zinc Hydroxide ◽

Scanning Calorimetry ◽

Sensing Properties ◽

Transmission Electron ◽

Porous Nanosheets ◽

Gas Sensing Properties

The ZnO microspheres constructed by porous nanosheets were successfully synthesized by calcinating zinc hydroxide carbonate (ZHC) microspheres obtained by a sample hydrothermal method. The samples were characterized in detail with scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), and thermogravimetric and differential scanning calorimetry (TG-DSC). The results indicated that the prepared ZnO microspheres were well crystalline with wurtzite hexagonal phase. The effects of reaction time, temperature, the amount of trisodium citrate, and urea on the morphology of ZnO microspheres were studied. The formation mechanism of porous ZnO microspheres was discussed. Furthermore, the gas-sensing properties for detection of organic gas of the prepared porous ZnO microspheres were investigated. The results indicated that the prepared porous ZnO microspheres exhibited high gas-sensing properties for detection of ethanol gas.

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Synthesis of Al Doped ZnO with a Novel Rice Microstructure by Hydrothermal Process and Analysis of their Gas Sensing Properties

Materials Science Forum ◽

10.4028/www.scientific.net/msf.809-810.724 ◽

2014 ◽

Vol 809-810 ◽

pp. 724-730

Author(s):

Zan Li ◽

Wei Qin ◽

Xiao Hong Wu

Keyword(s):

Electron Microscopy ◽

Gas Sensing ◽

Hydrothermal Process ◽

Hexagonal Wurtzite Structure ◽

X Ray ◽

Sensing Properties ◽

Transmission Electron ◽

Gas Sensing Properties ◽

Doped Zno ◽

Hydrothermal Approach

Al-doped ZnO (AZO) powers with a novel rice-like morphology have been successfully synthesized through a simple and efficient hydrothermal approach, the products have been characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) with an energy-dispersive X-ray analyzer and transmission electron microscopy (TEM). It showed that all the samples presented an hexagonal wurtzite structure of high crystallinity, and the microstructure was composed of numerous dumbbells. Furthermore, the heater gas sensors were fabricated and an investigation of gas sensing properties has been conducted. The sensors showed good selectivity to ethanol comparing with NH3, SO2, CO and HCHO and possible mechanism was discussed. The Sensors based AZO powers exhibited high response values, reproducible response-recovery to ethanol 50-1800 ppm at 332°C.

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The Microwave-Assisted Synthesis and Gas Sensing Properties for Ethanol of SnO2 Nanomaterials

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.721.237 ◽

2013 ◽

Vol 721 ◽

pp. 237-240 ◽

Cited By ~ 1

Author(s):

Yong Ju Liu ◽

Qiu Ping Jiang ◽

Yue Huan Li ◽

He Yun Zhao

Keyword(s):

Electron Microscopy ◽

Gas Sensing ◽

Microwave Assisted Synthesis ◽

X Ray Diffraction ◽

Sensing Properties ◽

Microwave Assisted ◽

Transmission Electron ◽

Good Crystalline Quality ◽

Gas Sensing Properties ◽

Microwave Assisted Method

With the advantages of the microwave-assisted method, good crystalline quality SnO2nanomaterials were successfully synthesized. The morphology and microstructure of SnO2were characterized by X-ray diffraction (XRD), scanning electron microscopy, transmission electron microscopy and high-resolution (HRTEM) used to examine SnO2nanomaterials. Indirect-heating sensors based on nanorods were fabricated and investigated for the gas sensing properties to ethanol. The investigation demonstrates that the sensor based on prepared SnO2nanomaterials has good sensitivity, low detection limit and short response and reversion time to ethanol at 275 °C.

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The Characterization and Gas Sensing Properties of Polythiophene Coated V2O5 Nanotubes

Materials Science Forum ◽

10.4028/www.scientific.net/msf.654-656.1154 ◽

2010 ◽

Vol 654-656 ◽

pp. 1154-1157 ◽

Cited By ~ 2

Author(s):

Yu Lu ◽

Wei Jin ◽

Wen Chen

Keyword(s):

Electron Microscopy ◽

Gas Sensing ◽

In Situ Polymerization ◽

X Ray Diffraction ◽

X Ray ◽

Sensing Properties ◽

Transmission Electron ◽

Gas Sensing Properties ◽

Higher Sensitivity

Polythiophene (PTP) coated V2O5 nanotubes were prepared by an in-situ polymerization of thiophene monomers in the presence of prepared V2O5 nanotubes. The nanotubes were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM), which proved the polymerization of thiophene monomer and the strong interaction between polythiophene and V2O5 nanotubes (VONTs). The gas sensing properties of PTP coated V2O5 nanotubes were studied at room temperature, which was found that PTP coated V2O5 nanotubes could detect ethanol with much higher sensitivity than pure VONTs. The sensing mechanism of PTP coated V2O5 nanotubes to ethanol is presumed to be the synergetic interaction between polythiophene (PTP) and V2O5 nanotubes.

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Growth, Characterization and Gas Sensing Properties of Nanotetrapod ZnO

Journal of Nanoscience and Nanotechnology ◽

10.1166/jnn.2008.an45 ◽

2008 ◽

Vol 8 (8) ◽

pp. 4106-4110 ◽

Cited By ~ 2

Author(s):

Manmeet Kaur ◽

Shovit Bhattacharya ◽

Vibha Saxena ◽

D. K. Aswal ◽

Mainak Roy ◽

...

Keyword(s):

Electron Microscopy ◽

Photoelectron Spectroscopy ◽

Gas Sensing ◽

Green Emission ◽

Near Band Edge ◽

X Ray ◽

Sensing Properties ◽

Selected Area Electron Diffraction ◽

Growth Characterization ◽

Gas Sensing Properties

ZnO nanotetrapods have been obtained in large quantities by carbothermal reduction of ZnO powder. These were characterized by X-ray diffraction, X-ray photoelectron spectroscopy, scanning electron microscopy, transmission electron microscopy, selected area electron diffraction, UV-visible spectroscopy and photoluminescence. Electron microscopy revealed that the overall size of the tetrapods is 1.5–2 μm and legs are 30–50 nm in diameter. The size of tetrapods as well as diameter of the legs was found to increase with deposition temperature. Photoluminescence spectra revealed that green emission originating from oxygen vacancies overwhelmed that of the near-band-edge ultraviolet peak. A band gap of 3.27 eV was calculated from optical absorption spectra which agreed well with that estimated from PL spectra. Gas sensing properties of tetrapods were investigated and these were found to be 5 times more sensitive to H2S gas at room temperature in comparison to ZnO bulk polycrystalline material.

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Oxygen vacancies-contained SnO2 nanotubes with enhanced ethanol gas sensing properties

International Journal of Modern Physics B ◽

10.1142/s0217979220400032 ◽

2019 ◽

Vol 34 (01n03) ◽

pp. 2040003 ◽

Cited By ~ 2

Author(s):

Yifan Chen ◽

Xiuling Ma ◽

Chen Li ◽

Qiuyu Wu ◽

Yongbo Wang ◽

...

Keyword(s):

Electron Microscopy ◽

High Performance ◽

Oxygen Vacancies ◽

Gas Sensing ◽

Original Sample ◽

X Ray Diffraction ◽

Sensing Properties ◽

Transmission Electron ◽

Gas Sensing Properties ◽

Ethanol Sensing

[Formula: see text] porous nanotubes containing oxygen vacancies were prepared by electron spinning and H plasma treatment. The morphology and crystal structure of the samples were analyzed by scanning electron microscopy (SEM), transmission electron microscopy (TEM) and X-ray diffraction (XRD). The ethanol-sensing properties of the [Formula: see text] sensor were tested. The results show that the samples treated with H plasma for 20 min have the best performance. Its working temperature is [Formula: see text]C lower than [Formula: see text]C of the original sample, with a sensitivity of 17 at 100 ppm, which is seven times higher than the original sample. It also shows good selectivity to some common interfering gases. This enhancement can be ascribed to the introduced oxygen vacancy. This work provides an efficient way to design high-performance gas sensor materials.

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A comparative study on the electrical and gas sensing properties of thick films prepared with synthesized nano-sized and commercial micro-sized Fe2O3 powders

Processing and Application of Ceramics ◽

10.2298/pac1704265m ◽

2017 ◽

Vol 11 (4) ◽

pp. 265-274 ◽

Cited By ~ 1

Author(s):

Ali Mirzaei ◽

Maryam Bonyani ◽

Shahab Torkian ◽

Mahdi Feizpour ◽

Anna Bonavita ◽

...

Keyword(s):

Electron Microscopy ◽

Gas Sensing ◽

Thick Films ◽

Sol Gel ◽

X Ray Diffraction ◽

Sensing Properties ◽

Sensing Applications ◽

Transmission Electron ◽

Gas Sensing Properties ◽

Underlying Mechanisms

In this work, Fe2O3 nanoparticles (NPs) were successfully synthesized by Pechini sol-gel method. Scanning electron microscopy, transmission electron microscopy and X-ray diffraction characterizations were used to study the morphology and crystal structure of the synthesized products. The electrical and gas sensing behaviour of the synthesized and commercial Fe2O3 samples, prepared in the form of thick films, were studied. Though the commercial Fe2O3 powders had lower resistance but it was found that the synthesized Fe2O3 NPs had better gas sensing properties. The underlying mechanisms are discussed in details. The present findings show advantages of Fe2O3 NPs over micro-size particles for gas sensing applications.

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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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