Large-scale Production of Selective Gas Sensors Based on Carbon Nanotube Mats Transistors

AbstractThe first paper showing the great potentiality of Carbon Nanotubes Field Effect transistors (CNTFETs) for gas sensing applications was published in 2000 [1]. It has been demonstrated that the performances of this kind of sensors are extremely interesting: a sensitivity of around 100ppt (e.g. for NO2 [2]) has been achieved in 2003 and several techniques to improve selectivity have been tested with very promising results [2]. The main issues that have not allowed, up to now, these devices to strike more largely the market of sensors, have been the lack of an industrial method to obtain low-cost devices, a demonstration of their selectivity in relevant environments and finally a deeper study on the effect of humidity and the possible solutions to reduce it. This contribution deals with CNTFETs based sensors fabricated using air-brush technique deposition on large surfaces. Compared to our last contribution [3], we have optimized the air-brush technique in order to obtain high performances transistors (Log(Ion)/Log(Ioff) ∼ 5/6) with highly reproducible characteristics : this is a key point for the industrial exploitation. We have developed a machine which allows us the dynamic deposition on heated substrates of the SWCNT solutions, improving dramatically the uniformity of the SWCNT mats. We have performed tests using different solvents that could be adapted as a function of the substrates (e.g. flexible substrates). Moreover these transistors have been achieved using different metal electrodes (patented approach [4]) in order to improve selectivity. Results of tests using NO2, NH3 with concentrations between ∼ 1ppm and 10ppm will be shown during the meeting.

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Printing polyaniline for sensor applications

Chemical Papers ◽

10.2478/s11696-012-0301-9 ◽

2013 ◽

Vol 67 (8) ◽

Cited By ~ 45

Author(s):

Karl Crowley ◽

Malcolm Smyth ◽

Anthony Killard ◽

Aoife Morrin

Keyword(s):

Conducting Polymer ◽

Inkjet Printing ◽

Large Scale ◽

Low Cost ◽

Clinical Diagnostics ◽

Scale Production ◽

Light Emitting ◽

Sensor Applications ◽

Sensing Applications ◽

Large Scale Production

AbstractIn recent years, much research has focused on the development of low-cost, printed electrochemical sensor platforms for environmental monitoring and clinical diagnostics. Much effort in this area has been based on utilising the redox properties of conducting polymers, particularly polyaniline (PANI). In tackling the inherent lack of processability exhibited by these materials, several groups have examined various mass-amenable fabrication approaches to obtain suitable thin films of PANI for sensing applications. Specifically, the approaches investigated over the years include the in situ chemical synthesis of PANI, the use of sulphonated derivatives of PANI and the synthesis of aqueousbased nano-dispersions of PANI. Nano-dispersions have shown a great deal of promise for sensing applications, given that they are inkjet-printable, facilitating the patterning of conducting polymer directly to the substrate. We have shown that inkjet-printed films of PANI can be finely controlled in terms of their two-dimensional pattern, thickness, and conductivity, highlighting the level of precision achievable by inkjet printing. Utilising these nanomaterials as inkjet-printable inks opens novel, facile, and economical possibilities for conducting polymer-printed electronic applications in areas of sensing, but also many other application areas such as energy storage, displays, organic light-emitting diodes. Given that inkjet-printing is a scalable manufacturing technique, it renders possible the large-scale production of devices such as sensors for a range of applications. Several successes have emerged from our work and from the work of others in the area of applying PANI in low-cost sensor applications, which is the focus of this review.

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A Review on Zinc Oxide Nanostructures: Doping and Gas Sensing

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.667.329 ◽

2013 ◽

Vol 667 ◽

pp. 329-332 ◽

Cited By ~ 11

Author(s):

A.N. Afaah ◽

Zuraida Khusaimi ◽

Mohamad Rusop

Keyword(s):

Large Scale ◽

Carrier Transport ◽

Gas Sensing ◽

Low Cost ◽

Scale Production ◽

Zno Nanostructures ◽

Zinc Oxide Nanostructures ◽

Oxide Nanostructures ◽

Large Scale Production ◽

Set Up

This paper presents a review on synthesis, structure, and growth mechanisms of one-dimensional nanostructures of ZnO. Solution-based method is a potential deposition technique for large-scale production as its advantages; the low cost, the simplicity of experimental set-up, and the low operating temperature. Mist-atomiser technique is one of the solution-based methods in synthesizing optimized ZnO nanostructures. Doping will lead for better properties of ZnO, which result to wide application area. Nanostructured ZnO is important in promising areas of application which devices utilizing nanostructures such as gas sensors and solar cells, since it is fairly easy to fabricate such forms of ZnO nanostructures, which have good charge carrier transport properties and high crystalline quality.

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Thermoelectric Performance of Mechanically Mixed BixSb2-xTe3—ABS Composites

Materials ◽

10.3390/ma14071706 ◽

2021 ◽

Vol 14 (7) ◽

pp. 1706

Author(s):

Zacharias Viskadourakis ◽

Argiri Drymiskianaki ◽

Vassilis M. Papadakis ◽

Ioanna Ioannou ◽

Theodora Kyratsi ◽

...

Keyword(s):

Polymer Composites ◽

Large Scale ◽

Low Cost ◽

Acrylonitrile Butadiene Styrene ◽

Thermoelectric Performance ◽

Scale Production ◽

Bismuth Antimony Telluride ◽

Mechanical Mixing ◽

Large Scale Production ◽

Bi Doping

In the current study, polymer-based composites, consisting of Acrylonitrile Butadiene Styrene (ABS) and Bismuth Antimony Telluride (BixSb2−xTe3), were produced using mechanical mixing and hot pressing. These composites were investigated regarding their electrical resistivity and Seebeck coefficient, with respect to Bi doping and BixSb2-xTe3 loading into the composite. Experimental results showed that their thermoelectric performance is comparable—or even superior, in some cases—to reported thermoelectric polymer composites that have been produced using other complex techniques. Consequently, mechanically mixed polymer-based thermoelectric materials could be an efficient method for low-cost and large-scale production of polymer composites for potential thermoelectric applications.

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Large Scale Production of Carbon Nanotube Transistors: A Generic Platform for Chemical Sensors

MRS Proceedings ◽

10.1557/proc-776-q12.7 ◽

2003 ◽

Vol 776 ◽

Cited By ~ 3

Author(s):

Jean-Christophe P. Gabriel

Keyword(s):

Chemical Sensors ◽

Large Scale ◽

Field Effect Transistors ◽

Chemical Vapor ◽

Scale Production ◽

Statistical Characterization ◽

Large Scale Production ◽

Nanotube Transistors ◽

New Formulation ◽

Nanotube Growth

AbstractWe report our work on the fabrication of nanotube-based field effect transistors (NTFET). Nanotubes were grown by chemical vapor deposition using various approaches, including a new formulation of nanotube growth catalysts that were directly patterned using UV lithography. We also report NTFETs based on randomly oriented nanotube networks that have a modulation of one. Finally, we report that a systematical and statistical characterization of millions of devices has led to the development of a robust process that may be useful in large scale production of reproducible, nanotube-based FETs, which, in turn, can be used as a generic platform for chemical sensors.

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Extensive Screening of Green Solvents for Safe and Sustainable UiO-66 Synthesis

10.26434/chemrxiv.12745097 ◽

2020 ◽

Author(s):

Diletta Morelli Venturi ◽

Filippo Campana ◽

Fabio Marmottini ◽

Ferdinando Costantino ◽

Luigi Vaccaro

Keyword(s):

Large Scale ◽

Low Cost ◽

Metal Organic Framework ◽

Dimethyl Formamide ◽

Scale Production ◽

Green Solvents ◽

High Quality ◽

Color Code ◽

Large Scale Production ◽

Metal Organic

Zirconium based Metal-Organic Framework UiO-66 is to date considered one of the benchmark compound among stable MOFs and it has attracted a huge attention for its employment in many strategic applications. Large scale production of UiO-66 for industrial purposes requires the use of safe and green solvents, fulfilling the green chemistry principles and able to replace the use of N,N-Dimethyl-Formamide (DMF), which, despite its toxicity, is still considered the most efficient solvent for obtaining UiO-66 of high quality. Herein we report on a survey of about 40 different solvents with different polarity, boiling point and acidity, used for the laboratory scale synthesis of high quality UiO-66 crystals. The solvents were chosen according the European REACH Regulation 1907/2006 among those having low cost, low toxicity and fully biodegradable. Concerning MOF synthesis, the relevant parameters chosen for establishing the quality of the results obtained are the degree are the crystallinity, microporosity and specific surface area, yield and solvent recyclability. Taking into account also the chemical physical properties of all the solvents, a color code was assigned in order to give a final green assessment for the UiO-66 synthesis. Defectivity of the obtained products, the use of acidic modulators and the use of alternative Zr-salts have been also taken into consideration. Preliminary results lead to conclude that GVL (γ-valerolactone) is among the most promising solvents for replacing DMF in UiO-66 MOF synthesis.

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Low-cost Large Scale Vermicompost Unit

Journal of Physics Conference Series ◽

10.1088/1742-6596/2115/1/012026 ◽

2021 ◽

Vol 2115 (1) ◽

pp. 012026

Author(s):

Sonam Solanki ◽

Gunendra Mahore

Keyword(s):

Large Scale ◽

Low Cost ◽

Small Scale ◽

Scale Production ◽

Key Innovation ◽

Main Challenge ◽

Long Run ◽

Large Scale Production ◽

Term Maintenance

Abstract In the current process of producing vermicompost on a large-scale, the main challenge is to keep the worms alive. This is achieved by maintaining temperature and moisture in their living medium. It is a difficult task to maintain these parameters throughout the process. Currently, this is achieved by building infrastructure but this method requires a large initial investment and long-run maintenance. Also, these methods are limited to small-scale production. For large-scale production, a unit is developed which utilises natural airflow with water and automation. The main aim of this unit is to provide favourable conditions to worms in large-scale production with very low investment and minimum maintenance in long term. The key innovation of this research is that the technology used in the unit should be practical and easy to adopt by small farmers. For long-term maintenance of the technology lesser number of parts are used.

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Extensive Screening of Green Solvents for Safe and Sustainable UiO-66 Synthesis

10.26434/chemrxiv.12745097.v1 ◽

2020 ◽

Author(s):

Diletta Morelli Venturi ◽

Filippo Campana ◽

Fabio Marmottini ◽

Ferdinando Costantino ◽

Luigi Vaccaro

Keyword(s):

Large Scale ◽

Low Cost ◽

Metal Organic Framework ◽

Dimethyl Formamide ◽

Scale Production ◽

Green Solvents ◽

High Quality ◽

Color Code ◽

Large Scale Production ◽

Metal Organic

Zirconium based Metal-Organic Framework UiO-66 is to date considered one of the benchmark compound among stable MOFs and it has attracted a huge attention for its employment in many strategic applications. Large scale production of UiO-66 for industrial purposes requires the use of safe and green solvents, fulfilling the green chemistry principles and able to replace the use of N,N-Dimethyl-Formamide (DMF), which, despite its toxicity, is still considered the most efficient solvent for obtaining UiO-66 of high quality. Herein we report on a survey of about 40 different solvents with different polarity, boiling point and acidity, used for the laboratory scale synthesis of high quality UiO-66 crystals. The solvents were chosen according the European REACH Regulation 1907/2006 among those having low cost, low toxicity and fully biodegradable. Concerning MOF synthesis, the relevant parameters chosen for establishing the quality of the results obtained are the degree are the crystallinity, microporosity and specific surface area, yield and solvent recyclability. Taking into account also the chemical physical properties of all the solvents, a color code was assigned in order to give a final green assessment for the UiO-66 synthesis. Defectivity of the obtained products, the use of acidic modulators and the use of alternative Zr-salts have been also taken into consideration. Preliminary results lead to conclude that GVL (γ-valerolactone) is among the most promising solvents for replacing DMF in UiO-66 MOF synthesis.

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Porous micro-spherical LiFePO4/CNT nanocomposite for high-performance Li-ion battery cathode material

RSC Advances ◽

10.1039/c5ra05988g ◽

2015 ◽

Vol 5 (47) ◽

pp. 37830-37836 ◽

Cited By ~ 12

Author(s):

Wei Wei ◽

Linlin Guo ◽

Xiaoyang Qiu ◽

Peng Qu ◽

Maotian Xu ◽

...

Keyword(s):

Electrochemical Performance ◽

Cathode Material ◽

High Performance ◽

Large Scale ◽

Low Cost ◽

Scale Production ◽

Li Ion Battery ◽

Excellent Performance ◽

Large Scale Production ◽

Li Ion

Although many routes have been developed that can efficiently improve the electrochemical performance of LiFePO4 cathodes, few of them meet the urgent industrial requirements of large-scale production, low cost and excellent performance.

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Nanocrystalline Materials for Hybrid Photovoltaic Devices

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.1116.45 ◽

2015 ◽

Vol 1116 ◽

pp. 45-50

Author(s):

Tarek I.A. Mashreki ◽

Mohammad Afzaal

Keyword(s):

Solar Cells ◽

Large Scale ◽

Low Cost ◽

Scale Production ◽

Photovoltaic Devices ◽

Large Scale Production ◽

Semiconductor Nanomaterials ◽

Inorganic Semiconductor ◽

Thin Film Composites ◽

Film Composites

Nanocomposites containing inorganic semiconductor nanomaterials are of tremendous interest for low-cost 3rd generation solar cells. A variety of possible materials and structures could be potentially used to reduce processing costs which is highly attractive for large scale production of solar cells. Controlling the morphology and surface chemistry of nanomaterials remains a key challenge that has major knock-on effects in devices. Herein, an attempt is made to highlight some of the challenges and the possible solutions for depositing high quality thin film composites for solar cell devices.

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