Single step deposition of different morphology ZnO gas sensing films

Tungsten trioxide (WO3) nanostructure with aspect ratio of 20 (length/diameter) have been successfully synthesized by single step hydrothermal reaction at moderate temperature of 180 °C. The crystal structure and morphology evolution are characterized by SEM and Raman while the carbon dioxide (CO2) sensing capability was tested by simple sensor fabrication .It was observed that the nanorods were initially coalesce in bundles before breaking up loosely towards the end of the hydrothermal process. A response measurement reveals that the sensor was able to detect CO2 at room temperature with the sensitivity around 13ohm/100 ppm. The detection performance of such nanostructure provides a positive indication that it can be a competitive sensor element candidate not only for CO2 applications in particular but can be expanded to other gas sensing application such as O2, C2H4 and NO2.

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Single-Step, Low-Temperature Simultaneous Formations and in Situ Binding of Tin Oxide Nanoparticles to Graphene Nanosheets by In-Liquid Plasma for Potential Applications in Gas Sensing and Lithium-Ion Batteries

ACS Applied Nano Materials ◽

10.1021/acsanm.8b02201 ◽

2019 ◽

Vol 2 (2) ◽

pp. 649-654 ◽

Cited By ~ 5

Author(s):

Ranjit R. Borude ◽

Hirotsugu Sugiura ◽

Kenji Ishikawa ◽

Takayoshi Tsutsumi ◽

Hiroki Kondo ◽

...

Keyword(s):

Low Temperature ◽

Tin Oxide ◽

Gas Sensing ◽

Graphene Nanosheets ◽

Lithium Ion ◽

Single Step ◽

Oxide Nanoparticles ◽

Potential Applications ◽

Tin Oxide Nanoparticles

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Fabrication of ZnO Bridging Nanowire Device by a Single-Step Chemical Vapor Deposition Method

MRS Proceedings ◽

10.1557/proc-1144-ll17-03 ◽

2008 ◽

Vol 1144 ◽

Author(s):

Yanbo Li ◽

Ippei Nagatomo ◽

Ryohei Uchino ◽

Ichiro Yamada ◽

Jean-Jacques Delaunay

Keyword(s):

Chemical Vapor Deposition ◽

Vapor Deposition ◽

Gas Sensing ◽

Gold Catalyst ◽

Chemical Vapor ◽

High Sensitivity ◽

Single Step ◽

Zno Nanowires ◽

Oxide Semiconductor ◽

Chemical Vapor Deposition Method

ABSTRACTZnO nanowires are directly integrated into a working device by a single-step chemical vapor deposition (CVD) method. Gold catalyst is patterned on a quartz glass substrate using a comb-shaped shadow mask and then ZnO is grown on the patterned substrate by CVD. Thick ZnO layers formed on the gold-patterned areas serve as native electrodes. Ultra-long (˜100 μm) ZnO nanowires grown across the gap between the ZnO electrodes and the nanowires serve as the sensing elements of the device. The device exhibits high sensitivity and fast response to UV illumination in air. Our method can be used to fabricate other metal oxide semiconductor bridging nanowire devices, which have promising applications in photodetection and gas sensing.

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Ultra-Rapid CO Gas Detection by a Gas Sensor Based on Flame-Spray-Made Pt/ZnO Nanoparticles

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.421-422.332 ◽

2009 ◽

Vol 421-422 ◽

pp. 332-335 ◽

Cited By ~ 2

Author(s):

Nittaya Tamaekong ◽

Chaikarn Liewhiran ◽

Anurat Wisitsoraat ◽

Sukon Phanichphant

Keyword(s):

Zno Nanoparticles ◽

Gas Sensing ◽

Zno Nanorods ◽

Single Step ◽

Flame Spray ◽

Al2o3 Substrate ◽

Particle Properties ◽

Gas Sensing Properties ◽

Crystallite Sizes ◽

20 Nm

ZnO nanoparticles doped with 0.2-2 at.%Pt were successfully produced in a single step by flame spray pyrolysis (FSP) technique using zinc naphthenate and platinum (II) acetylacetonate dissolved in xylene. The particle properties were analyzed by XRD, BET and TEM. Depending on FSP conditions, ZnO nanoparticles and nanorods were observed. The crystallite sizes of ZnO spheroidal particles were found to be ranging from 5 to 20 nm, while ZnO nanorods were seen to be 5-20 nm in width and 20-40 nm in length. ZnO sensing films were prepared using Al2O3 substrate interdigitated with Au electrodes by spin-coating technique. The gas sensing properties toward carbon monoxide (CO) was studied at the operating temperatures ranging from 200 to 350°C. It was found that the 0.2 at.%Pt/ZnO sensing film showed the highest sensitivity and the fastest response time at 350°C.

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Edge-Hydrogenated Germanene by Electrochemical Decalcification-Exfoliation of CaGe2: Germanene-Enabled Vapor Sensor

10.26434/chemrxiv.14483457.v1 ◽

2021 ◽

Author(s):

Evgeniya Kovalska ◽

Nikolas Antonatos ◽

Jan Luxa ◽

Zdenek Sofer

Keyword(s):

Gas Sensing ◽

Chemical Properties ◽

Single Step ◽

Synthetic Methods ◽

Aqueous Environment ◽

Free Standing ◽

New Approach ◽

Vapor Sensing ◽

Vapor Sensor ◽

First Time

<p><a>Two-dimensional germanene has been recently explored for applications in sensing, catalysis, and energy storage. The potential of this material lies on its graphene-like optoelectronic and chemical properties. However, pure free-standing germanene cannot be found in nature and the synthetic methods are hindering the potentially fascinating properties of germanene. </a>Herein, <a>we report for the first time a single-step synthesis of few-layer germanene by electrochemical exfoliation in non-aqueous environment. As a result of simultaneous decalcification and intercalation of the electrolyte’s active ions, we achieved a low-level hydrogenation of germanene that occurs at the edges of the material. The obtained edge-hydrogenated germanene flakes have a lateral size of several micrometers which possess a cubic structure. We have pioneered the potential application of edge-hydrogenated germanene for vapor sensing and demonstrated its specific sensitivity to methanol and ethanol. We have shown a selective behavior of the germanene-based sensor that appears to increase the electrical resistance in the vapors where methanol prevails. We anticipate that these results can provide a new approach for emerging layered materials with the potential utility in advanced gas sensing.</a></p>

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Effect of AuPd Bimetal Sensitization on Gas Sensing Performance of Nanocrystalline SnO2 Obtained by Single Step Flame Spray Pyrolysis

Nanomaterials ◽

10.3390/nano9050728 ◽

2019 ◽

Vol 9 (5) ◽

pp. 728 ◽

Cited By ~ 2

Author(s):

Valeriy Krivetskiy ◽

Konstantin Zamanskiy ◽

Artemiy Beltyukov ◽

Andrey Asachenko ◽

Maxim Topchiy ◽

...

Keyword(s):

Spray Pyrolysis ◽

Gas Sensor ◽

Gas Sensing ◽

Chemical Reactivity ◽

Medical Diagnostics ◽

Single Step ◽

Industrial Safety ◽

Flame Spray Pyrolysis ◽

Flame Spray ◽

Level Control

Improvement of sensitivity, lower detection limits, stability and reproducibility of semiconductor metal oxide gas sensor characteristics are required for their application in the fields of ecological monitoring, industrial safety, public security, express medical diagnostics, etc. Facile and scalable single step flame spray pyrolysis (FSP) synthesis of bimetal AuPd sensitized nanocrystalline SnO2 is reported. The materials chemical composition, structure and morphology has been studied by XRD, XPS, HAADFSTEM, BET, ICP-MS techniques. Thermo-programmed reduction with hydrogen (TPR-H2) has been used for materials chemical reactivity characterization. Superior gas sensor response of bimetallic modified SnO2 towards wide concentration range of reducing (CO, CH4, C3H8, H2S, NH3) and oxidizing (NO2) gases compared to pure and monometallic modified SnO2 is reported for dry and humid gas detection conditions. The combination of facilitated oxygen molecule spillover on gold particles and electronic effect of Fermi level control by reoxidizing Pd-PdO clusters on SnO2 surface is proposed to give rise to the observed enhanced gas sensor performance.

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