Synthesis of g-C3N4 nanosheet modified SnO2 composites with improved performance for ethanol gas sensing

A high performance gas sensor based on a metal phthalocyanine/graphene quantum dot hybrid material was fabricated for NO2 detection at room-temperature.

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Star-Fruit-Shaped CuO Structures for High Performance Ethanol Gas Sensor Device

Science of Advanced Materials ◽

10.1166/sam.2021.3968 ◽

2021 ◽

Vol 13 (4) ◽

pp. 724-733

Author(s):

Ahmad Umar ◽

Ahmed A. Ibrahim ◽

Rajesh Kumar ◽

Hassan Algadi ◽

Hasan Albargi ◽

...

Keyword(s):

Gas Sensor ◽

High Performance ◽

Crystal Size ◽

Gas Sensing ◽

Sensor Applications ◽

Sensor Device ◽

Star Fruit ◽

Micro Structures ◽

Gas Response ◽

Structural Crystal

In this paper, star-fruit-shaped CuO microstructures were hydrothermally synthesized and subsequently characterized through different techniques to understand morphological, compositional, structural, crystal, optical and vibrational properties. The formation of star-fruit-shaped structures along with some polygonal and spherical nanostructures was confirmed by FESEM analysis. XRD data and Raman spectrum confirmed the monoclinic tenorite crystalline phase of the CuO with crystal size 17.61 nm. Star-fruit-shaped CuO microstructures were examined for ethanol gas sensing behavior at various operating temperatures and concentrations. The gas response of 135% was observed at the optimal temperature of 225 °C. Due to excellent selectivity, stability and re-usability, the as-fabricated sensor based on star-fruit-shaped CuO micro-structures may be explored for future toxic gas sensor applications.

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Design and Synthesis of Novel 2D Porous Zinc Oxide-Nickel Oxide Composite Nanosheets for Detecting Ethanol Vapor

Nanomaterials ◽

10.3390/nano10101989 ◽

2020 ◽

Vol 10 (10) ◽

pp. 1989

Author(s):

Yuan-Chang Liang ◽

Yen-Cheng Chang ◽

Wei-Cheng Zhao

Keyword(s):

Zinc Oxide ◽

Nickel Oxide ◽

Active Sites ◽

Gas Sensing ◽

Ethanol Vapor ◽

Gas Diffusion ◽

High Specific Surface Area ◽

Sputtering Deposition ◽

Vapor Sensing ◽

Sensing Performance

The porous zinc oxide-nickel oxide (ZnO-NiO) composite nanosheets were synthesized via sputtering deposition of NiO thin film on the porous ZnO nanosheet templates. Various NiO film coverage sizes on porous ZnO nanosheet templates were achieved by changing NiO sputtering duration in this study. The microstructures of the porous ZnO-NiO composite nanosheets were investigated herein. The rugged surface feature of the porous ZnO-NiO composite nanosheets were formed and thicker NiO coverage layer narrowed the pore size on the ZnO nanosheet template. The gas sensors based on the porous ZnO-NiO composite nanosheets displayed higher sensing responses to ethanol vapor in comparison with the pristine ZnO template at the given target gas concentrations. Furthermore, the porous ZnO-NiO composite nanosheets with the suitable NiO coverage content demonstrated superior gas-sensing performance towards 50–750 ppm ethanol vapor. The observed ethanol vapor-sensing performance might be attributed to suitable ZnO/NiO heterojunction numbers and unique porous nanosheet structure with a high specific surface area, providing abundant active sites on the surface and numerous gas diffusion channels for the ethanol vapor molecules. This study demonstrated that coating of NiO on the porous ZnO nanosheet template with a suitable coverage size via sputtering deposition is a promising route to fabricate porous ZnO-NiO composite nanosheets with a high ethanol vapor sensing ability.

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Copper oxide hierarchical morphology derived from MOF precursors for enhancing ethanol vapor sensing performance

Journal of Materials Chemistry C ◽

10.1039/d0tc01425g ◽

2020 ◽

Vol 8 (28) ◽

pp. 9671-9677 ◽

Cited By ~ 2

Author(s):

Sha Wang ◽

Zhimin Gao ◽

Guoshuai Song ◽

Yantao Yu ◽

Wenxiu He ◽

...

Keyword(s):

Copper Oxide ◽

Structure Function ◽

Gas Sensing ◽

Ethanol Vapor ◽

Vapor Sensing ◽

Structure Function Relationship ◽

Function Relationship ◽

Relationship Of ◽

Hierarchical Morphology ◽

Sensing Performance

The structure–function relationship of CuO hierarchical morphologies in gas sensing has been revealed.

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Defect-Controlled Gas Sensing Property of Nanostructured ZnO Films

Materials Science Forum ◽

10.4028/www.scientific.net/msf.814.54 ◽

2015 ◽

Vol 814 ◽

pp. 54-59

Author(s):

Yong Qin Chang ◽

Chang Jing Shao ◽

Nan Jiang ◽

Yan Jun Ma ◽

Shi Qi Wang ◽

...

Keyword(s):

Gas Sensor ◽

Oxygen Vacancies ◽

Gas Sensing ◽

Chemical Vapor ◽

Zno Films ◽

Sensor Applications ◽

Cvd Method ◽

Short Recovery Time ◽

Gas Sensing Properties ◽

Ethanol Sensing

Nanostructured ZnO films were fabricated by chemical vapor deposition (CVD) method with different Sn source concentrations for ethanol sensing application. It was found that the morphology of the ZnO films were obviously affected by Sn concentration, while no any Sn signals were detected in the films. The response of the nanostructured ZnO films increases with the increase of ethanol concentrations, and the S2 sample displays the highest sensitivity. Thephotoluminescence spectra show that more oxygen vacancies exist in the S2 sample than the other samples, which reveals that oxygen vacancies may play a great role to improve the gas sensing properties of the ZnO films.A possible sensing mechanism was proposed to explain these phenomena.This work provides a very simple and efficient method to prepare ZnO gas sensor, its high response and short recovery time are also a merit for the ZnO films used in gas sensor applications.

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High Performance Acetylene Sensor with Heterostructure Based on WO3 Nanolamellae/Reduced Graphene Oxide (rGO) Nanosheets Operating at Low Temperature

Nanomaterials ◽

10.3390/nano8110909 ◽

2018 ◽

Vol 8 (11) ◽

pp. 909 ◽

Cited By ~ 8

Author(s):

Zikai Jiang ◽

Weigen Chen ◽

Lingfeng Jin ◽

Fang Cui ◽

Zihao Song ◽

...

Keyword(s):

Graphene Oxide ◽

Reduced Graphene Oxide ◽

Gas Sensor ◽

High Performance ◽

Gas Sensing ◽

Hybrid Nanocomposites ◽

Transformer Oil ◽

X Ray ◽

Reduced Graphene ◽

Sensing Performance

The development of functionalized metal oxide/reduced graphene oxide (rGO) hybrid nanocomposites concerning power equipment failure diagnosis is one of the most recent topics. In this work, WO3 nanolamellae/reduced graphene oxide (rGO) nanocomposites with different contents of GO (0.5 wt %, 1 wt %, 2 wt %, 4 wt %) were synthesized via controlled hydrothermal method. X-ray diffraction (XRD), transmission electron microscopy (TEM), Raman spectroscopy, X-ray photoelectron spectroscopy (XPS), thermogravimetric analyses-derivative thermogravimetric analysis-differential scanning calorimetry (TG-DTG-DSC), BET, and photoluminescence (PL) spectroscopy were utilized to investigate morphological characterizations of prepared gas sensing materials and indicated that high quality WO3 nanolamellae were widely distributed among graphene sheets. Experimental ceramic planar gas sensors composing of interdigitated alumina substrates, Au electrodes, and RuO2 heating layer were coated with WO3 nanolamellae/reduced graphene oxide (rGO) films by spin-coating technique and then tested for gas sensing towards multi-concentrations of acetylene (C2H2) gases in a carrier gas with operating temperature ranging from 50 °C to 400 °C. Among four contents of prepared samples, sensing materials with 1 wt % GO nanocomposite exhibited the best C2H2 sensing performance with lower optimal working temperature (150 °C), higher sensor response (15.0 toward 50 ppm), faster response-recovery time (52 s and 27 s), lower detection limitation (1.3 ppm), long-term stability, and excellent repeatability. The gas sensing mechanism for enhanced sensing performance of nanocomposite is possibly attributed to the formation of p-n heterojunction and the active interaction between WO3 nanolamellae and rGO sheets. Besides, the introduction of rGO nanosheets leads to the impurity of synthesized materials, which creates more defects and promotes larger specific area for gas adsorption, outstanding conductivity, and faster carrier transport. The superior gas sensing properties of WO3/rGO based gas sensor may contribute to the development of a high-performance ppm-level gas sensor for the online monitoring of dissolved C2H2 gas in large-scale transformer oil.

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Environmentally Friendly and Cost-Effective Synthesis of Carbonaceous Particles for Preparing Hollow SnO2 Nanospheres and their Bifunctional Li-Storage and Gas-Sensing Properties

Crystals ◽

10.3390/cryst10030231 ◽

2020 ◽

Vol 10 (3) ◽

pp. 231

Author(s):

Yingyi Ding ◽

Ping Zhou ◽

Tianli Han ◽

Jinyun Liu

Keyword(s):

Gas Sensor ◽

Gas Sensing ◽

Coulombic Efficiency ◽

Hollow Spheres ◽

Lithium Ion ◽

Environmentally Friendly ◽

Cost Effective ◽

Carbonaceous Particles ◽

Research Fields ◽

Effective Synthesis

The templated preparation of hollow nanomaterials has received broad attention. However, many templates are expansive, environmentally-harmful, along with involving a complicated preparation process. Herein, we present a cost-effective, environmentally friendly and simple approach for making carbonaceous particles which have been demonstrated as efficient templates for preparing hollow nanospheres. Natural biomass, such as wheat or corn, is used as the source only, and thus other chemicals are not needed. The carbonaceous particles possess abundant hydroxyl and carboxyl groups, enabling them to efficiently adsorb metal ions in solution. The prepared SnO2 hollow spheres were used in a lithium-ion (Li-ion) battery anode, and as the sensing layer of a gas sensor, respectively. After charge–discharge for 200 times at a rate of 1 C, the anodes exhibit a stable capacity of 500 mAh g−1, and a Coulombic efficiency as high as 99%. In addition, the gas sensor based on the SnO2 hollow spheres shows a high sensing performance towards ethanol gas. It is expected that the presented natural biomass-derived particles and their green preparation method will find more applications for broad research fields, including energy-storage and sensors.

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New Design of ZnO Nanorod- and Nanowire-Based NO2 Room-Temperature Sensors Prepared by Hydrothermal Method

Journal of Nanomaterials ◽

10.1155/2019/6821937 ◽

2019 ◽

Vol 2019 ◽

pp. 1-9 ◽

Cited By ~ 9

Author(s):

Vo Thanh Duoc ◽

Dang Thi Thanh Le ◽

Nguyen Duc Hoa ◽

Nguyen Van Duy ◽

Chu Manh Hung ◽

...

Keyword(s):

Hydrothermal Method ◽

Room Temperature ◽

Gas Sensing ◽

Local Heating ◽

Zno Nanorods ◽

Hydrothermal Process ◽

Maximal Response ◽

Sensor Applications ◽

Sensing Characteristics ◽

Sensing Performance

Room-temperature gas sensors are attracting attention because of their low power consumption, safe operation, and long-term stability. Herein, ZnO nanorods (NRs) and nanowires (NWs) were on-chip grown via a facile hydrothermal method and used for room-temperature NO2 gas sensor applications. The ZnO NRs were obtained by a one-step hydrothermal process, whereas the NWs were obtained by a two-step hydrothermal process. To obtain ZnO NW sensor, the length of NRs was controlled short enough so that none of the nanorod-nanorod junction was made. Thereafter, the NWs were grown from the tips of no-contact NRs to form nanowire-nanowire junctions. The gas-sensing characteristics of ZnO NRs and NWs were tested against NO2 gas at room temperature for comparison. The gas-sensing characteristics of the sensors were also tested at different applied voltages to evaluate the effect of the self-activated gas-sensing performance. Results show that the diameter of ZnO NRs and NWs is the dominant parameter of their NO2 gas-sensing performance at room temperature. In addition, self-activation by local heating occurred for both sensors, but because the NWs were smaller and sparser than the NRs, local heating thus required a lower applied voltage with maximal response compared with the NRs.

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Xylene gas sensor based on Ni doped TiO2 bowl-like submicron particles with enhanced sensing performance

RSC Advances ◽

10.1039/c5ra01395j ◽

2015 ◽

Vol 5 (36) ◽

pp. 28105-28110 ◽

Cited By ~ 29

Author(s):

Linghui Zhu ◽

Dezhong Zhang ◽

Ying Wang ◽

Caihui Feng ◽

Jingran Zhou ◽

...

Keyword(s):

Gas Sensor ◽

Gas Sensing ◽

Submicron Particles ◽

Doped Tio2 ◽

Sensing Performance

Bowl-like TiO2 submicron particles prepared by electrospray technique were used to detect xylene gas and Ni element was added into TiO2 to improve the gas sensing performances.

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Development of Indium Titanium Zinc Oxide Thin Films Used as Sensing Layer in Gas Sensor Applications

Coatings ◽

10.3390/coatings11070807 ◽

2021 ◽

Vol 11 (7) ◽

pp. 807

Author(s):

Sheng-Po Chang ◽

Ren-Hao Yang ◽

Chih-Hung Lin

Keyword(s):

Thin Films ◽

Gas Sensor ◽

Gas Sensors ◽

Gas Sensing ◽

Uv Light ◽

Rf Sputtering ◽

Metal Structure ◽

Sensor Applications ◽

Long Term Stability ◽

Sensing Technology

InTiZnO gas sensors with different oxygen ratios were fabricated by RF sputtering at room temperature. The sensing responses for five different gases, including ethanol, isopropanol (IPA), acetone (ACE), CO, and SO2, were reported. The InTiZnO gas sensor with the MSM (metal–semiconductor–metal) structure generated a higher sensing response when the O2/Ar ratio was increased to 10%. It also revealed high selectivity among these gases and good repeatability. Moreover, the UV light-activated InTiZnO gas sensors were also studied, which could reduce the operating temperature from 300 °C to 150 °C and did not seem to damage the sensing film, demonstrating long-term stability. The high response and selectivity revealed that InTiZnO thin films possess high potential to be applied in gas sensing technology.

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