scholarly journals Bridging Nanowires for Enhanced Gas Sensing Properties

Crystals ◽  
2021 ◽  
Vol 11 (7) ◽  
pp. 743
Author(s):  
Mohammad R Alenezi ◽  
Abdullah M. Almeshal
Keyword(s):  
High Performance ◽  
Gas Sensing ◽  
Fast Response ◽  
Growth Environment ◽  
Enhanced Sensitivity ◽  
Gas Sensing Properties ◽  
Response And Recovery ◽  
Nanowire Sensor ◽  
On Chip ◽  
Site Selective

It is crucial to develop new bottom-up fabrication methods with control over the physical properties of the active materials to produce high-performance devices. This article reports well-controlled, without seed layer and site-selective hydrothermal method to produce ZnO bridging nanowires sensors. By controlling the growth environment, the performance of the sensor became more efficient. The presented on-chip bridging nanowire sensor enhanced sensitivity toward acetone gas (200 ppm) around 63 and fast response time (420 ms) and recovery time (900 ms). The enhancement in the speed of response and recovery is ascribed to the exceptional NW-NW junction barrier that governs the sensor’s conductivity, and the excellent contact between ZnO nanowires and Au electrodes.

scholarly journals MOFs-Derived Porous NiFe2O4 Nano-Octahedrons with Hollow Interiors for an Excellent Toluene Gas Sensor

Nanomaterials ◽  
2019 ◽  
Vol 9 (8) ◽  
pp. 1059 ◽  
Author(s):  
Yanlin Zhang ◽  
Chaowei Jia ◽  
Qiuyue Wang ◽  
Quan Kong ◽  
Gang Chen ◽  
...  
Keyword(s):  
Gas Sensing ◽  
Metal Organic Framework ◽  
Fast Response ◽  
Sensing Properties ◽  
Gas Sensing Properties ◽  
Metal Organic ◽  
Response And Recovery ◽  
Nife2o4 Nanoparticles ◽  
Gas Molecules ◽  
Ppm Level

Toluene is extensively used in many industrial products, which needs to be effectively detected by sensitive gas sensors even at low-ppm-level concentrations. Here, NiFe2O4 nano-octahedrons were calcinated from NiFe-bimetallic metal-organic framework (MOFs) octahedrons synthesized by a facile refluxing method. The co-existence of p-Phthalic acid (PTA) and 3,3-diaminobenzidine (DAB) promotes the formation of smooth NiFe-bimetallic MOFs octahedrons. After subsequent thermal treatment, a big weight loss (about 85%) transformed NiFe2O4 nanoparticles (30 nm) into NiFe2O4 porous nano-octahedrons with hollow interiors. The NiFe2O4 nano-octahedron based sensor exhibited excellent gas sensing properties for toluene with a nice stability, fast response, and recovery time (25 s/40 s to 100 ppm toluene), and a lower detection limitation (1 ppm) at 260 °C. The excellent toluene-sensing properties can not only be derived from the hollow interiors combined with porous nano-octahedrons to favor the diffusion of gas molecules, but also from the efficient catalytic activity of NiFe2O4 nanoparticles.

Improved gas sensing properties of silver-functionalized ZnSnO3 hollow nanocubes

2018 ◽  
Vol 5 (9) ◽  
pp. 2123-2131 ◽  
Author(s):  
YanYang Yin ◽  
Feng Li ◽  
Nan Zhang ◽  
Shengping Ruan ◽  
Haifeng Zhang ◽  
...  
Keyword(s):  
Gas Sensor ◽  
Gas Sensing ◽  
Fast Response ◽  
Sensing Properties ◽  
Gas Sensing Properties ◽  
Response And Recovery ◽  
Porous Silver ◽  
Acetone Detection

Porous silver-functionalized ZnSnO3 hollow nanocubes as a gas sensor with an ultra-fast response and recovery speed for acetone detection.

Enhanced Gas Sensing of Tin Dioxide Based Sensor for Indoor Formaldehyde Application

2021 ◽  
Vol 16 (2) ◽  
pp. 337-342
Author(s):  
Gaoqi Zhang ◽  
Fan Zhang ◽  
Kaifang Wang ◽  
Shanyu Liu ◽  
Ying Wang ◽  
...  
Keyword(s):  
Gas Sensors ◽  
Tin Dioxide ◽  
Gas Sensing ◽  
Fast Response ◽  
Sensing Material ◽  
Gas Sensing Properties ◽  
Recovery Times ◽  
Response And Recovery ◽  
Formaldehyde Sensing ◽  
Gas Response

Indoor formaldehyde detection is of great important at present. Using efficient solvothermal method, nanosheet-constructed and nanorod-constructed hierarchical tin dioxide (SnO2) microspheres were successfully synthesized in this work and used for the gas sensing material for indoor formaldehyde application. The as-prepared two kinds of SnO2 gas sensing materials were applied to fabricate the gas sensors and formaldehyde gas sensing experiments were carried out. The HCHO gas sensing tests indicate that the gas response of the nanosheet-constructed SnO2 microspheres is about 1.7 times higher than that of the nanorod-constructed SnO2 microspheres. In addition, both of the two SnO2 based gas sensors show almost fast response and recovery time to HCHO gas. For the nanosheet-constructed microspheres, the response value is estimated to be 32.0 at 350 °C to 60 ppm formaldehyde gas, while the response and recovery times are 7 and 5 s, respectively. The simple and efficient preparation method and improved gas sensing properties show that the as-synthesized hierarchical SnO2 microsphere that is constructed by a large amount of nanosheets exhibits significant potential application for the indoor formaldehyde sensing.

scholarly journals Facile Chemical Bath Synthesis of SnS Nanosheets and Their Ethanol Sensing Properties

Sensors ◽  
2019 ◽  
Vol 19 (11) ◽  
pp. 2581 ◽  
Author(s):  
Wei Shan ◽  
Zhengqian Fu ◽  
Mingsheng Ma ◽  
Zhifu Liu ◽  
Zhenggang Xue ◽  
...  
Keyword(s):  
High Performance ◽  
Gas Sensing ◽  
Raw Materials ◽  
Orthorhombic Phase ◽  
Ethanol Vapor ◽  
Fast Response ◽  
Sensing Applications ◽  
Recovery Times ◽  
Response And Recovery ◽  
Ethanol Sensing

Tin(II) monosulfide (SnS) nanosheets were synthesized using SnCl4•5H2O and S powders as raw materials in the presence of H2O via a facile chemical bath method. Orthorhombic phase SnS nanosheets with a thickness of ~100 nm and lateral dimensions of 2~10 μm were obtained by controlling the synthesis parameters. The formation of a SnO2 intermediate is key to the valence reduction of Sn ions (from IV to II) and the formation of SnS. The gas sensors fabricated from SnS nanosheets exhibited an excellent response of 14.86 to 100 ppm ethanol vapor when operating at 160 °C, as well as fast response and recovery times of 23 s and 26 s, respectively. The sensors showed excellent selectivity for the detection of ethanol over acetone, methanol, and ammonia gases, which indicates the SnS nanosheets are promising for high-performance ethanol gas sensing applications.

scholarly journals Fast Response Isopropanol Sensing Properties with Sintered BiFeO3 Nanocrystals

Materials ◽  
2020 ◽  
Vol 13 (17) ◽  
pp. 3829 ◽  
Author(s):  
Hongxiang Xu ◽  
Junhua Xu ◽  
Junlin Wei ◽  
Yamei Zhang
Keyword(s):  
Gas Sensing ◽  
Fast Response ◽  
Gas Detection ◽  
Detection Range ◽  
Sensing Properties ◽  
Working Temperature ◽  
Sensing Material ◽  
Gas Sensing Properties ◽  
Response And Recovery ◽  
Optimum Working

BiFeO3 nanocrystals were applied as the sensing material to isopropanol. The isopropanol sensor based on BiFeO3 nanocrystals shows excellent gas-sensing properties at the optimum working temperature of 240 °C. The sensitivity of as-prepared sensor to 100 ppm isopropanol is 31 and its response and recovery time is as fast as 6 and 17 s. The logarithmic curves of the sensitivity and concentration of BiFeO3 sensors are a very good linear in the low detection range of 2–100 ppm. In addition, the gas sensing mechanism is also discussed. The results suggest that the BiFeO3 nanomaterial can be potentially applied in isopropanol gas detection.

scholarly journals Nanostructured TiO2-based gas sensors with enhanced sensitivity to reducing gases

2016 ◽  
Vol 7 ◽  
pp. 1718-1726 ◽  
Author(s):  
Wojciech Maziarz ◽  
Anna Kusior ◽  
Anita Trenczek-Zajac
Keyword(s):  
Thin Films ◽  
Gas Sensing ◽  
High Sensitivity ◽  
Fast Response ◽  
Enhanced Sensitivity ◽  
3D Nanostructures ◽  
Structure Morphology ◽  
Gas Sensing Properties ◽  
Reducing Gases ◽  
Acetone Sensor

2D TiO2 thin films and 3D flower-like TiO2-based nanostructures, also decorated with SnO2, were prepared by chemical and thermal oxidation of Ti substrates, respectively. The crystal structure, morphology and gas sensing properties of the TiO2-based sensing materials were investigated. 2D TiO2 thin films crystallized mainly in the form of rutile, while the flower-like 3D nanostructures as anatase. The sensor based on the 2D TiO2 showed the best performance for H2 detection, while the flower-like 3D nanostructures exhibited enhanced selectivity to CO(CH3)2 after sensitization by SnO2 nanoparticles. The sensor response time was of the order of several seconds. Their fast response, high sensitivity to selected gas species, improved selectivity and stability suggest that the SnO2-decorated flower-like 3D nanostructures are a promising material for application as an acetone sensor.

scholarly journals Enhancing Formaldehyde Selectivity of SnO2 Gas Sensors with the ZSM-5 Modified Layers

Sensors ◽  
2021 ◽  
Vol 21 (12) ◽  
pp. 3947
Author(s):  
Wei Wang ◽  
Qinyi Zhang ◽  
Ruonan Lv ◽  
Dong Wu ◽  
Shunping Zhang
Keyword(s):  
Gas Sensors ◽  
Indoor Air ◽  
High Performance ◽  
Screen Printing ◽  
Gas Sensing ◽  
Oxide Semiconductors ◽  
Screen Printing Method ◽  
Gas Sensing Properties ◽  
Zeolite Films ◽  
Insufficient Knowledge

High performance formaldehyde gas sensors are widely needed for indoor air quality monitoring. A modified layer of zeolite on the surface of metal oxide semiconductors results in selectivity improvement to formaldehyde as gas sensors. However, there is insufficient knowledge on how the thickness of the zeolite layer affects the gas sensing properties. In this paper, ZSM-5 zeolite films were coated on the surface of the SnO2 gas sensors by the screen printing method. The thickness of ZSM-5 zeolite films was controlled by adjusting the numbers of screen printing layers. The influence of ZSM-5 film thickness on the performance of ZSM-5/SnO2 gas sensors was studied. The results showed that the ZSM-5/SnO2 gas sensors with a thickness of 19.5 μm greatly improved the selectivity to formaldehyde, and reduced the response to ethanol, acetone and benzene at 350 °C. The mechanism of the selectivity improvement to formaldehyde of the sensors was discussed.

Fast response acetone-sensing properties of SnO2 nanoparticles prepared by the sol-gel method

2021 ◽  
Vol 93 (3) ◽  
pp. 30401
Author(s):  
Jiaxing Wang ◽  
Hai Yu ◽  
Yong Zhang
Keyword(s):  
High Performance ◽  
Gas Sensing ◽  
Sno2 Nanoparticles ◽  
Sol Gel ◽  
Fast Response ◽  
X Ray Diffraction ◽  
Gel Method ◽  
Sol Gel Method ◽  
Short Recovery Time ◽  
Acetone Gas Detection

SnO2 nanoparticle architectures were successfully synthesized using a sol-gel method and developed for acetone gas detection. The morphology and structure of the particles were characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM). The SnO2 nanoparticle architectures were configured as high-performance sensors to detect acetone and showed a very fast response time (<1 s), a short recovery time (10 s), good repeatability and high selectivity at a relatively low working temperature. Thus, SnO2 nanoparticles should be promising candidates for designing and fabricating acetone gas sensors with good gas sensing performance. The possible gas sensing mechanism is also presented.

scholarly journals Advanced Strategies to Improve Performances of Molybdenum-Based Gas Sensors

2021 ◽  
Vol 13 (1) ◽  
Author(s):  
Angga Hermawan ◽  
Ni Luh Wulan Septiani ◽  
Ardiansyah Taufik ◽  
Brian Yuliarto ◽  
Suyatman ◽  
...  
Keyword(s):  
High Performance ◽  
Gas Sensing ◽  
Low Cost ◽  
Molybdenum Oxides ◽  
Exhaled Breath ◽  
Sensor Applications ◽  
Theoretical Investigations ◽  
Gas Sensing Properties ◽  
Future Challenges ◽  
Made In

AbstractMolybdenum-based materials have been intensively investigated for high-performance gas sensor applications. Particularly, molybdenum oxides and dichalcogenides nanostructures have been widely examined due to their tunable structural and physicochemical properties that meet sensor requirements. These materials have good durability, are naturally abundant, low cost, and have facile preparation, allowing scalable fabrication to fulfill the growing demand of susceptible sensor devices. Significant advances have been made in recent decades to design and fabricate various molybdenum oxides- and dichalcogenides-based sensing materials, though it is still challenging to achieve high performances. Therefore, many experimental and theoretical investigations have been devoted to exploring suitable approaches which can significantly enhance their gas sensing properties. This review comprehensively examines recent advanced strategies to improve the nanostructured molybdenum-based material performance for detecting harmful pollutants, dangerous gases, or even exhaled breath monitoring. The summary and future challenges to advance their gas sensing performances will also be presented.

Preparation and Property of Lanthanum Ferrite Formaldehyde Gas Sensor Modified by Carbon Nanotubes and Silver

2013 ◽  
Vol 320 ◽  
pp. 554-557 ◽  
Author(s):  
Yu Min Zhang ◽  
Yu Tao Lin ◽  
Jin Zhang ◽  
Zhong Qi Zhu ◽  
Qiang Liu ◽  
...  
Keyword(s):  
Carbon Nanotubes ◽  
Chemical Synthesis ◽  
Recovery Time ◽  
Gas Sensing ◽  
Operating Temperature ◽  
Sol Gel ◽  
Lanthanum Ferrite ◽  
Gas Sensing Properties ◽  
Response And Recovery ◽  
Sensitive Property

Our previous study revealed that the gas sensitive property of Silver-modified Lanthanum Ferrite (Ag-LaFeO3) is well, but the operating temperature is still high and the sensitivity also needs to be improved. This work based on our previous study. Ag-LaFeO3 was further modified by the Carbon nanoTubes (CNTs). The Ag-LaFeO3 powder modified with CNTs (CNTs-Ag-LaFeO3) was prepared by a sol-gel method combined with microwave chemical synthesis. The structure and gas-sensing properties were investigated. The results show that the structure of CNTs-Ag-LaFeO3 is of orthogonal perovskite. The sensitivity of 0.75% CNTs-Ag-LaFeO3 powder for 1 ppm formaldehyde is 13 at 86°C. The response and recovery time are 100s and 60s, respectively. Moreover, the sensor also has an obvious response for 1ppm formaldehyde at 58°C.

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