Enhanced Propanol Gas Sensing Performance of p-type NiO Gas Sensor Induced by Exceptionally Large Surface Area and Crystallinity

Porous Pt decorated anatase/rutile sensing nanospheres with high crystallinity and large surface area synthesized through psHT treatment present enhanced sensitivity and selectivity to VOCs vapor at room temperature.

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Moderate-temperature operable SO<sub>2</sub> gas sensor based on Zr<sup>4+</sup> ion conducting solid electrolyte

Journal of Sensors and Sensor Systems ◽

10.5194/jsss-1-29-2012 ◽

2012 ◽

Vol 1 (1) ◽

pp. 29-32

Author(s):

Y. Uneme ◽

S. Tamura ◽

N. Imanaka

Keyword(s):

Sulfur Dioxide ◽

Solid Electrolyte ◽

Surface Area ◽

Gas Sensor ◽

Gas Sensing ◽

Reference Electrode ◽

Rapid Response ◽

Large Surface Area ◽

Ion Conducting ◽

So2 Gas

Abstract. A solid electrolyte type sulfur dioxide (SO2) gas sensor that can operate at moderate temperatures was fabricated using Zr4+ ion conducting Zr39/40TaP2.9W0.1O12 solid electrolyte with 0.7La2O2SO4 − 0.3(0.8Li2SO4 + 0.2K2SO4) having a large surface area and Zr metal as the auxiliary sensing electrode and reference electrode, respectively. Since the present sensor showed a quantitative, reproducible and rapid response which obeys the theoretical Nernst relationship even at 400 °C, it is a potential on site SO2 gas sensing tool operable at moderate temperatures around 400 °C.

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Enhancing room-temperature NO2 gas sensing performance based on a metal phthalocyanine/graphene quantum dot hybrid material

RSC Advances ◽

10.1039/d0ra10310a ◽

2021 ◽

Vol 11 (10) ◽

pp. 5618-5628

Author(s):

Wenkai Jiang ◽

Xinwei Chen ◽

Tao Wang ◽

Bolong Li ◽

Min Zeng ◽

...

Keyword(s):

Quantum Dot ◽

Gas Sensor ◽

Hybrid Material ◽

High Performance ◽

Room Temperature ◽

Gas Sensing ◽

Metal Phthalocyanine ◽

Graphene Quantum Dot ◽

Sensing Performance

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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Large-surface-area 3D self-assembled nano-porous structure for high-sensitivity gas-sensing

2011 16th International Solid-State Sensors, Actuators and Microsystems Conference ◽

10.1109/transducers.2011.5969832 ◽

2011 ◽

Cited By ~ 3

Author(s):

M. Abasaki ◽

K. Yamada ◽

S. Souma ◽

N. Moronuki ◽

M. Sugiyama

Keyword(s):

Porous Structure ◽

Surface Area ◽

Gas Sensing ◽

High Sensitivity ◽

Large Surface Area ◽

Self Assembled

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Simple post-synthesis of mesoporous p-type Co3O4 nanochains for enhanced H2S gas sensing performance

Sensors and Actuators B Chemical ◽

10.1016/j.snb.2018.05.026 ◽

2018 ◽

Vol 270 ◽

pp. 158-166 ◽

Cited By ~ 26

Author(s):

Pham Long Quang ◽

Nguyen Duc Cuong ◽

Tran Thai Hoa ◽

Hoang Thai Long ◽

Chu Manh Hung ◽

...

Keyword(s):

Gas Sensing ◽

Post Synthesis ◽

P Type ◽

Sensing Performance

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Preparation and Application of 2D MXene-Based Gas Sensors: A Review

Chemosensors ◽

10.3390/chemosensors9080225 ◽

2021 ◽

Vol 9 (8) ◽

pp. 225

Author(s):

Qingting Li ◽

Yanqiong Li ◽

Wen Zeng

Keyword(s):

Composite Materials ◽

Specific Surface ◽

Surface Area ◽

Gas Sensor ◽

Specific Surface Area ◽

Gas Sensors ◽

Room Temperature ◽

Gas Sensing ◽

Interlayer Spacing ◽

Preparation Methods

Since MXene (a two-dimensional material) was discovered in 2011, it has been favored in all aspects due to its rich surface functional groups, large specific surface area, high conductivity, large porosity, rich organic bonds, and high hydrophilicity. In this paper, the preparation of MXene is introduced first. HF etching was the first etching method for MXene; however, HF is corrosive, resulting in the development of the in situ HF method (fluoride + HCl). Due to the harmful effects of fluorine terminal on the performance of MXene, a fluorine-free preparation method was developed. The increase in interlayer spacing brought about by adding an intercalator can affect MXene’s performance. The usual preparation methods render MXene inevitably agglomerate and the resulting yields are insufficient. Many new preparation methods were researched in order to solve the problems of agglomeration and yield. Secondly, the application of MXene-based materials in gas sensors was discussed. MXene is often regarded as a flexible gas sensor, and the detection of ppb-level acetone at room temperature was observed for the first time. After the formation of composite materials, the increasing interlayer spacing and the specific surface area increased the number of active sites of gas adsorption and the gas sensitivity performance improved. Moreover, this paper discusses the gas-sensing mechanism of MXene. The gas-sensing mechanism of metallic MXene is affected by the expansion of the lamellae and will be doped with H2O and oxygen during the etching process in order to become a p-type semiconductor. A p-n heterojunction and a Schottky barrier forms due to combinations with other semiconductors; thus, the gas sensitivities of composite materials are regulated and controlled by them. Although there are only several reports on the application of MXene materials to gas sensors, MXene and its composite materials are expected to become materials that can effectively detect gases at room temperature, especially for the detection of NH3 and VOC gas. Finally, the challenges and opportunities of MXene as a gas sensor are discussed.

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High-Performance Gas Sensor of Polyaniline/Carbon Nanotube Composites Promoted by Interface Engineering

Sensors ◽

10.3390/s20010149 ◽

2019 ◽

Vol 20 (1) ◽

pp. 149 ◽

Cited By ~ 9

Author(s):

Weiyu Zhang ◽

Shuai Cao ◽

Zhaofeng Wu ◽

Min Zhang ◽

Yali Cao ◽

...

Keyword(s):

High Performance ◽

Structural Changes ◽

Gas Sensing ◽

Response Times ◽

Limit Of Detection ◽

Hierarchical Structures ◽

Cost Effective ◽

One Dimensional ◽

P Type ◽

Sensing Performance

Inspired by the enhanced gas-sensing performance by the one-dimensional hierarchical structure, one-dimensional hierarchical polyaniline/multi-walled carbon nanotubes (PANI/CNT) fibers were prepared. Interestingly, the simple heating changed the sensing characteristics of PANI from p-type to n-type and n-type PANI and p-type CNTs form p–n hetero junctions at the core–shell interface of hierarchical PANI/CNT composites. The p-type PANI/CNT (p-PANI/CNT) and n-type PANI/CNT (n-PANI/CNT) performed the higher sensitivity to NO2 and NH3, respectively. The response times of p-PANI/CNT and n-PANI/CNT to 50 ppm of NO2 and NH3 are only 5.2 and 1.8 s, respectively, showing the real-time response. The estimated limit of detection for NO2 and NH3 is as low as to 16.7 and 6.4 ppb, respectively. After three months, the responses of p-PANI/CNT and n-PANI/CNT decreased by 19.1% and 11.3%, respectively. It was found that one-dimensional hierarchical structures and the deeper charge depletion layer enhanced by structural changes of PANI contributed to the sensitive and fast responses to NH3 and NO2. The formation process of the hierarchical PANI/CNT fibers, p–n transition, and the enhanced gas-sensing performance were systematically analyzed. This work also predicts the development prospects of cost-effective, high-performance PANI/CNT-based sensors.

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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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