Spinel-Type Materials Used for Gas Sensing: A Review

Demands for the detection of harmful gas in daily life have arisen for a period and a gas nano-sensor acting as a kind of instrument that can directly detect gas has been of wide concern. The spinel-type nanomaterial is suitable for the research of gas sensors because of its unique structure. However, the existing instability, higher detection limit, and operating temperature of the spinel materials limit the extension of the spinel material sensor. This paper reviews the research progress of spinel materials in gas sensor technology in recent years and lists the common morphological structures and material sensitization methods in combination with previous works.

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Xylene-sensing of Fe2(MoO4)3 nanoplates prepared via a hydrothermal method

Functional Materials Letters ◽

10.1142/s1793604717500229 ◽

2017 ◽

Vol 10 (03) ◽

pp. 1750022 ◽

Cited By ~ 5

Author(s):

Mengying Xu ◽

Zhidong Lin ◽

Wenying Guo ◽

Yuyuan Hong ◽

Ping Fu ◽

...

Keyword(s):

Gas Sensors ◽

Gas Sensing ◽

Operating Temperature ◽

Hydrothermal Process ◽

Optimum Operating ◽

Average Crystalline Size ◽

Optimum Operating Temperature ◽

Recovery Times ◽

Response And Recovery ◽

Simple Hydrothermal Process

Fe2(MoO4)3 nanoplates were prepared via a simple hydrothermal process. The average crystalline size of these nanoplates is 85.8[Formula: see text]nm. The sensor based on Fe2(MoO4)3 shows a high gas sensing performance to xylene. The response of Fe2(MoO4)3 sensor is 25.9–100[Formula: see text]ppm xylene at optimum operating temperature of 340[Formula: see text]C. The response and recovery times to 100[Formula: see text]ppm xylene are 4 and 10[Formula: see text]s, respectively. Furthermore, the Fe2(MoO4)3 sensor exhibits remarkable selectivity detection of xylene gas with negligible responses to toluene and benzene. Therefore, the Fe2(MoO4)3 is a promising material for the detection of xylene gas sensors.

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SnO2 Nano/Microfibers for Gas Sensors

Defect and Diffusion Forum ◽

10.4028/www.scientific.net/ddf.405.324 ◽

2020 ◽

Vol 405 ◽

pp. 324-329

Author(s):

Erika Mudra ◽

Ivan Shepa ◽

Alexandra Kovalcikova ◽

Ondrej Milkovič ◽

Jan Dusza

Keyword(s):

Gas Sensors ◽

Gas Sensing ◽

Operating Temperature ◽

Band Gap Energy ◽

Calcination Process ◽

Sensing Applications ◽

Amorphous Nature ◽

Coating Method ◽

Type Semiconductor

SnO2 is an n-type semiconductor with the band gap energy of 3.6 eV. It has been widely studied for gas sensing applications, the sensitivity of which can be easily tuned by the operating temperature. The presented paper is focused on the preparation and detailed characterization of the hollow SnO2 nano/microfibers suitable for gas detection sensors. Ceramic SnO2 fibers were produced by needleless electrospinning and followed by the calcination process. The characterization was performed by SEM, TEM, XRD, and Raman spectroscopy. The precursor PVP/SnO2 fibers had amorphous nature. The calcination of the electro spun precursor resulted in the formation of hollow crystalline fibrous structures. The formation mechanism of hollow fibers has been described. Subsequently, a homogeneous fibrous layer was created by the spin coating method for gas sensing applications.

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Synthesis, Structural and Gas Sensing Characterization of W-Doped SnO2 Nanostructures

Defect and Diffusion Forum ◽

10.4028/www.scientific.net/ddf.381.15 ◽

2017 ◽

Vol 381 ◽

pp. 15-19 ◽

Cited By ~ 1

Author(s):

Mukesh Chander Bhatnagar ◽

Anima Johari

Keyword(s):

Low Temperature ◽

Gas Sensors ◽

Gas Sensing ◽

Operating Temperature ◽

Environmental Pollutants ◽

Sensor Response ◽

Gas Content ◽

Temperature Sensitive ◽

Oxide Material ◽

Industry Waste

Tin oxide material has been extensively used for gas sensing application. Due to high operating temperature of metal oxide gas sensors, around 600 K and long term instability, research has been carried out to improve the material properties and reducing operating temperature. nanostructure materials have shown higher sensitivity and better stability towards gas environment. Air pollutants from automobiles and industry waste are the primary sources of environmental pollutants and there is need to develop low temperature, sensitive and selective gas sensors to monitor the gas content. In this paper, we have discussed the effect of Tungsten (W) doping in SnO2 nanostructures on the structural and gas sensing properties. The nanostructures have been synthesized by thermal evaporation process. The structural and surface morphology studies confirm the growth of nanowires on silicon substrates. The corresponding EDX spectra also confirm the doping of W into SnO2 nanowires. The gas sensor response of W-doped SnO2 nanowires was investigated upon exposure to various gases. It has been observed that doping of W enhances the NO2 sensitivity of nanowire based sensors at low temperature and the sensor response improves with increase in gas concentration.

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Fiber Optic Gas Sensors Based on Lossy Mode Resonances and Sensing Materials Used Therefor: A Comprehensive Review

Sensors ◽

10.3390/s21030731 ◽

2021 ◽

Vol 21 (3) ◽

pp. 731

Author(s):

Ignacio Vitoria ◽

Carlos Ruiz Zamarreño ◽

Aritz Ozcariz ◽

Ignacio R. Matias

Keyword(s):

Optical Fiber ◽

Gas Sensors ◽

Gas Sensing ◽

Optical Fiber Sensors ◽

Industrial Sector ◽

Fiber Sensors ◽

Sensing Applications ◽

Wide Range ◽

Materials Used ◽

Diagnostic Applications

Pollution in cities induces harmful effects on human health, which continuously increases the global demand of gas sensors for air quality control and monitoring. In the same manner, the industrial sector requests new gas sensors for their productive processes. Moreover, the association between exhaled gases and a wide range of diseases or health conditions opens the door for new diagnostic applications. The large number of applications for gas sensors has permitted the development of multiple sensing technologies. Among them, optical fiber gas sensors enable their utilization in remote locations, confined spaces or hostile environments as well as corrosive or explosive atmospheres. Particularly, Lossy Mode Resonance (LMR)-based optical fiber sensors employ the traditional metal oxides used for gas sensing purposes for the generation of the resonances. Some research has been conducted on the development of LMR-based optical fiber gas sensors; however, they have not been fully exploited yet and offer optimal possibilities for improvement. This review gives the reader a complete overview of the works focused on the utilization of LMR-based optical fiber sensors for gas sensing applications, summarizing the materials used for the development of these sensors as well as the fabrication procedures and the performance of these devices.

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Research Progress of MoS2 Composite rGO Material in Gas Sensor

E3S Web of Conferences ◽

10.1051/e3sconf/202126702048 ◽

2021 ◽

Vol 267 ◽

pp. 02048

Author(s):

Jiang Huaning ◽

Wang Huaizhang ◽

Liang Ting

Keyword(s):

Gas Sensors ◽

Materials Science ◽

Single Layer ◽

Reference Value ◽

Research Progress ◽

Single Layer Graphene ◽

Two Dimensional ◽

Preparation Methods ◽

Two Dimensional Materials ◽

Materials Used

Since the successful preparation of single-layer graphene in 2004, two-dimensional materials have gradually become one of the research hotspots in the field of materials science. However, due to the inevitable defects of intrinsic two-dimensional materials, researchers began to explore how to obtain more excellent two-dimensional materials. In this paper, the basic properties, preparation methods and application in gas sensors of MoS2/rGO composites are reviewed. This paper has a certain reference value for the research of two-dimensional materials used in gas sensors.

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Semiconductor Gas Sensors: Materials, Technology, Design, and Application

Sensors ◽

10.3390/s20226694 ◽

2020 ◽

Vol 20 (22) ◽

pp. 6694

Author(s):

Maria Vesna Nikolic ◽

Vladimir Milovanovic ◽

Zorka Z. Vasiljevic ◽

Zoran Stamenkovic

Keyword(s):

Carbon Nanotubes ◽

Transition Metal ◽

Conducting Polymers ◽

Metal Oxides ◽

Gas Sensors ◽

Gas Sensing ◽

Operating Temperature ◽

2D Materials ◽

Semiconductor Materials ◽

Technology Design

This paper presents an overview of semiconductor materials used in gas sensors, their technology, design, and application. Semiconductor materials include metal oxides, conducting polymers, carbon nanotubes, and 2D materials. Metal oxides are most often the first choice due to their ease of fabrication, low cost, high sensitivity, and stability. Some of their disadvantages are low selectivity and high operating temperature. Conducting polymers have the advantage of a low operating temperature and can detect many organic vapors. They are flexible but affected by humidity. Carbon nanotubes are chemically and mechanically stable and are sensitive towards NO and NH3, but need dopants or modifications to sense other gases. Graphene, transition metal chalcogenides, boron nitride, transition metal carbides/nitrides, metal organic frameworks, and metal oxide nanosheets as 2D materials represent gas-sensing materials of the future, especially in medical devices, such as breath sensing. This overview covers the most used semiconducting materials in gas sensing, their synthesis methods and morphology, especially oxide nanostructures, heterostructures, and 2D materials, as well as sensor technology and design, application in advance electronic circuits and systems, and research challenges from the perspective of emerging technologies.

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Growth Mechanisms of ZnO Micro-Nanomorphologies and Their Role in Enhancing Gas Sensing Properties

Sensors ◽

10.3390/s21041331 ◽

2021 ◽

Vol 21 (4) ◽

pp. 1331 ◽

Cited By ~ 1

Author(s):

Ambra Fioravanti ◽

Pietro Marani ◽

Sara Morandi ◽

Stefano Lettieri ◽

Mauro Mazzocchi ◽

...

Keyword(s):

Gas Sensors ◽

Gas Sensing ◽

Functional Materials ◽

Synthesis Process ◽

Growth Mechanisms ◽

Sensing Properties ◽

Wet Chemical Synthesis ◽

Gas Sensing Properties ◽

Materials Used ◽

Chemiresistive Gas Sensors

Zinc oxide (ZnO) is one of the main functional materials used to realize chemiresistive gas sensors. In addition, ZnO can be grown through many different methods obtaining the widest family of unique morphologies. However, the relationship between the ZnO morphologies and their gas sensing properties needs more detailed investigations, also with the aim to improve the sensor performances. In this work, seven nanoforms (such as leaves, bisphenoids, flowers, needles, etc.) were prepared through simple wet chemical synthesis. Morphological and structural characterizations were performed to figure out their growth mechanisms. Then, the obtained powders were deposited through screen-printing technique to realize thick film gas sensors. The gas sensing behavior was tested toward some traditional target gases and some volatile organic compounds (acetone, acetaldehyde, etc.) and compared with ZnO morphologies. Results showed a direct correlation between the sensors responses and the powders features (morphology and size), which depend on the specific synthesis process. The sensors can be divided in two behavioral classes, following the two main morphology kinds: aggregates of nanocrystals (leaves and bisphenoids), exhibiting best performances versus all tested gases and monocrystal based (stars, needle, long needles, flowers, and prisms).

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Gas Sensing Performance of 2D Nanomaterials/Metal Oxide Nanocomposites: A Review

Journal of Materials Chemistry C ◽

10.1039/d1tc01857d ◽

2021 ◽

Author(s):

Vijendra Singh Bhati ◽

Mahesh Kumar ◽

Rupak Banerjee

Keyword(s):

Metal Oxide ◽

Gas Sensors ◽

Industrial Production ◽

Gas Sensing ◽

Material Selection ◽

Daily Life ◽

2D Nanomaterials ◽

Sensing Performance

In recent years, the utilization of gas sensors has increased tremendously in daily life as well as industrial production. Importantly, appropriate material selection is imperative for gas sensors in order...

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Room-Temperature Gas Sensors Under Photoactivation: From Metal Oxides to 2D Materials

Nano-Micro Letters ◽

10.1007/s40820-020-00503-4 ◽

2020 ◽

Vol 12 (1) ◽

Cited By ~ 2

Author(s):

Rahul Kumar ◽

Xianghong Liu ◽

Jun Zhang ◽

Mahesh Kumar

Keyword(s):

Gas Sensor ◽

Gas Sensors ◽

Room Temperature ◽

Gas Sensing ◽

Sensor Technology ◽

Light Illumination ◽

Oxide Semiconductors ◽

Sensor Applications ◽

Two Dimensional Materials ◽

Important Approach

AbstractRoom-temperature gas sensors have aroused great attention in current gas sensor technology because of deemed demand of cheap, low power consumption and portable sensors for rapidly growing Internet of things applications. As an important approach, light illumination has been exploited for room-temperature operation with improving gas sensor’s attributes including sensitivity, speed and selectivity. This review provides an overview of the utilization of photoactivated nanomaterials in gas sensing field. First, recent advances in gas sensing of some exciting different nanostructures and hybrids of metal oxide semiconductors under light illumination are highlighted. Later, excellent gas sensing performance of emerging two-dimensional materials-based sensors under light illumination is discussed in details with proposed gas sensing mechanism. Originated impressive features from the interaction of photons with sensing materials are elucidated in the context of modulating sensing characteristics. Finally, the review concludes with key and constructive insights into current and future perspectives in the light-activated nanomaterials for optoelectronic gas sensor applications.

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