Hybrid multiwalled carbon nanotubes and trioxide tungsten nanoparticles for hydrogen gas sensing

A simple approach to the in situ deposition of well-crystallized SnO2nanocrystals on the surface of multiwalled carbon nanotubes (MWCNTs) in the ethanol solution system of SnCl2 was presented in this paper. The well-crystallized SnO2nanocrystals with small and uniform crystal size (4~5 nm) can be tightly and homogenously coated on the outside surface of the MWCNTs entirely. The prepared nanocomposites were characterized by X-ray diffraction, transmission electron microscopy, X-ray photoelectron spectroscopy, and nitrogen BET measurements. It is found that the hydrothermal reaction plays an important role for the crystal growth of the SnO2nanocrystals on the surface of MWCNTs, and the crystallinity of the SnO2nanocrystals can be controlled by varying the pH value or the hydrothermal reaction time. It is found that a unique structure of leaf-like SnO2nanosheets hanging on the MWCNTs was obtained when using water as the solvent of SnCl2instead of ethanol. The gas sensing performance of the SnO2/MWCNTs nanocomposites was also investigated.

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Tunable Chemical Grafting of Three-Dimensional Poly (3, 4-ethylenedioxythiophene)/Poly (4-styrenesulfonate)-Multiwalled Carbon Nanotubes Composite with Faster Charge-Carrier Transport for Enhanced Gas Sensing Performance

Sensors ◽

10.3390/s20092470 ◽

2020 ◽

Vol 20 (9) ◽

pp. 2470

Author(s):

Hyojae Kim ◽

Yeongseok Jang ◽

Gyeong Won Lee ◽

Seung Yun Yang ◽

Jinmu Jung ◽

...

Keyword(s):

Carbon Nanotubes ◽

Charge Carrier ◽

Multiwalled Carbon Nanotubes ◽

Carrier Transport ◽

Gas Sensing ◽

Three Dimensional ◽

Charge Carrier Transport ◽

Multiwalled Carbon ◽

Gas Molecules ◽

Sensing Performance

The three-dimensional volumetric application of conductive poly (3,4-ethylenedioxythiophene)/poly (4-styrenesulfonate) (PEDOT:PSS) to multiwalled carbon nanotubes (MWCNTs) has not been widely reported. In this study, the applicability of the 3D PEDOT:PSS-MWCNT composite for a gas sensor was investigated with different PEDOT:PSS concentrations. The gas-sensing performance of the 3D PEDOT:PSS-MWCNT composites was investigated using ethanol and carbon monoxide (CO) gas. Overall, in comparison with the pristine MWCNTs, as the PEDOT:PSS concentration increased, the 3D PEDOT:PSS-MWCNT composites exhibited increased conductivity and enhanced gas sensing performances (fast response and recovery times) to both ethanol and CO gases. Importantly, although the PEDOT:PSS coating layer reduced the number of sites for the adsorption and desorption of gas molecules, the charge-carrier transport between the gas molecules and MWCNTs was significantly enhanced. Thus, PEDOT:PSS can be chemically grafted to MWCNTs to enhance the connectivity and conductivity of a 3D network, leading to possible applications in gas sensors.

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Enhancement of Gas Sensing Characteristics of Multiwalled Carbon Nanotubes by CF4Plasma Treatment for SF6Decomposition Component Detection

Journal of Nanomaterials ◽

10.1155/2015/171545 ◽

2015 ◽

Vol 2015 ◽

pp. 1-9 ◽

Cited By ~ 1

Author(s):

Xiaoxing Zhang ◽

Xiaoqing Wu ◽

Bing Yang ◽

Hanyan Xiao

Keyword(s):

Carbon Nanotubes ◽

Multiwalled Carbon Nanotubes ◽

Recovery Time ◽

Treatment Time ◽

Gas Sensing ◽

Gas Sensitivity ◽

Multiwalled Carbon ◽

State Evaluation ◽

Response And Recovery ◽

Sensing Characteristics

H2S and SO2are important gas components of decomposed SF6of partial discharge generated by insulation defects in gas-insulated switchgear (GIS). Therefore, H2S and SO2detection is important in the state evaluation and fault diagnosis of GIS. In this study, dielectric barrier discharge was used to generate CF4plasma and modify multiwalled carbon nanotubes (MWNTs). The nanotubes were plasma-treated at optimum discharge conditions under different treatment times (0.5, 1, 2, 5, 8, 10, and 12 min). Pristine and treated MWNTs were used as gas sensors to detect H2S and SO2. The effects of treatment time on gas sensitivity were analyzed. Results showed that the sensitivity, response, and recovery time of modified MWNTs to H2S were improved, but the recovery time of SO2was almost unchanged. At 10 min treatment time, the MWNTs showed good stability and reproducibility with better gas sensing properties compared with the other nanotubes.

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