Enhancement of the gas sensing performance of carbon nanotube networked films based on their electrophoretic functionalization with gold nanoparticles

2015 ◽  
Vol 1786 ◽  
pp. 37-42 ◽  
Author(s):  
E. Dilonardo ◽  
M. Penza ◽  
M. Alvisi ◽  
C. Di Franco ◽  
D. Suriano ◽  
...  
Keyword(s):  
Gas Sensors ◽  
Gas Sensing ◽  
Gas Sensitivity ◽  
Sensing Applications ◽  
Active Layers ◽  
Resistive Gas Sensors ◽  
Ppm Level ◽  
Fine Tune ◽  
Pollutant Gases ◽  
Higher Sensitivity

ABSTRACTControlled amounts of colloidal Au nanoparticles (NPs), electrochemically pre-synthesized, were directly deposited on MWCNTs sensor devices by electrophoresis. Pristine and Au-functionalized MWCNT networked films were tested as active layers in resistive gas sensors for detection of pollutant gases. Au-modified CNT-chemiresistor demonstrated higher sensitivity to NO2 detecting up to sub-ppm level compared to pristine one. The investigation of the cross-sensitivity towards other pollutant gases revealed the decrease of the sensitivity to NO2 with the increase of Au content, and, on the other side, the increase of that to H2S; therefore the fine tune of the metal loading on CNTs has allowed to control not only the gas sensitivity but also the selectivity towards a specific gaseous analyte. Finally, the sensing properties of Au-decorated CNT sensor seem to be promising in environmental and automotive gas sensing applications, based on low power consumption and moderate operating temperature.

Gas Sensing Properties of Columnar CeO2 Nanostructures Prepared by Chemical Vapor Deposition

2008 ◽  
Vol 8 (2) ◽  
pp. 1012-1016 ◽  
Author(s):  
Davide Barreca ◽  
Elisabetta Comini ◽  
Alberto Gasparotto ◽  
Chiara Maccato ◽  
Cinzia Maragno ◽  
...  
Keyword(s):  
Chemical Vapor Deposition ◽  
Gas Sensors ◽  
Vapor Deposition ◽  
Gas Sensing ◽  
Chemical Vapor ◽  
Operating Conditions ◽  
Working Temperature ◽  
Gas Sensing Properties ◽  
Resistive Gas Sensors ◽  
Higher Sensitivity

Columnar CeO2 nanostructures are grown on alumina substrates by a template- and catalyst-free Chemical Vapor Deposition (CVD) approach and subsequently tested as resistive gas sensors of CH3COCH3, H2, NO2. The sensor response is stable and reproducible throughout the whole working temperature range (200–500 °C) and directly dependent on the analyte gas and the adopted operating conditions. The higher sensitivity with respect to that displayed by continuous CeO2 thin films demonstrates the potential of fabricating nanostructured sensing devices characterized by improved functional performances.

Controlled electrochemical functionalization of MOx nanostructures by Au NPs for gas sensing application

2015 ◽  
Vol 1805 ◽  
Author(s):  
E. Dilonardo ◽  
M. Penza ◽  
M. Alvisi ◽  
C. Di Franco ◽  
F. Palmisano ◽  
...  
Keyword(s):  
Gas Sensors ◽  
Gas Sensing ◽  
Operating Temperature ◽  
Low Cost ◽  
Sacrificial Anode ◽  
Au Nps ◽  
Active Layers ◽  
One Step ◽  
Sensing Application ◽  
Resistive Gas Sensors

ABSTRACTStabilized Au NPs were directly deposited on nanostructured ZnO and ZrO2 by a simple one-step strategy based on sacrificial anode electrolysis. The annealed nanocomposites are proposed as active layers in resistive gas sensors for low-cost processes. Results on the performance of gas sensors based on pristine and Au-doped MOx nanostructured thin films, used for the detection of NO2 gas, were reported at an operating temperature of 300°C, evaluating the effects of the MOx chemical composition and morphology, and the Au-doping.

scholarly journals Surface Modification of Carbon Nanotube Networked Films with Au Nanoclusters for Enhanced Gas Sensing Applications

2008 ◽  
Vol 2008 ◽  
pp. 1-8 ◽  
Author(s):  
M. Penza ◽  
R. Rossi ◽  
M. Alvisi ◽  
G. Cassano ◽  
M. A. Signore ◽  
...  
Keyword(s):  
Carbon Nanotube ◽  
Gas Sensing ◽  
Chemical Vapor ◽  
Gas Sensitivity ◽  
Multiwalled Carbon ◽  
Sensing Applications ◽  
Sensor Temperature ◽  
P Type ◽  
Gas Response ◽  
Ppm Level

Multiwalled carbon nanotube (MWCNT) films have been deposited by using plasma-enhanced chemical vapor deposition (PECVD) system onto alumina substrates, provided with 6 nm thick cobalt (Co) growth catalyst for remarkably improved gas sensing, at working temperature in the range of 100–. Functionalization of the MWCNTs with nanoclusters of gold (Au) sputtering has been performed to modify the surface of carbon nanotube networked films for enhanced and specific gas detection up to sub-ppm level. It is demonstrated that the gas sensitivity of the MWCNT-based sensors depends on Au-loading used as surface-catalyst. The gas response of MWCNT-based chemiresistor is attributed top-typeconductivity in the Au-modified semiconducting MWCNTs with a very good short-term repeatability and faster recovery. The sensor temperature of maximum sensitivity of the Au-functionalized MWCNTs is found to decrease with increasing Au-loading on their surface, and continuous gas monitoring at ppb level of is effectively performed with Au-modified MWCNT chemiresistors.

Metal-oxide based ammonia gas sensors: A review

2020 ◽  
Vol 10 ◽  
Author(s):  
Priya Gupta ◽  
Savita Maurya ◽  
Narendra Kumar Pandey ◽  
Vernica Verma
Keyword(s):  
Metal Oxide ◽  
Metal Oxides ◽  
Gas Sensor ◽  
Gas Sensors ◽  
Review Paper ◽  
Gas Sensing ◽  
Gas Sensitivity ◽  
Ammonia Gas ◽  
Ammonia Sensing ◽  
Ammonia Gas Sensors

: This review paper encompasses a study of metal-oxide and their composite based gas sensors used for the detection of ammonia (NH3) gas. Metal-oxide has come into view as an encouraging choice in the gas sensor industry. This review paper focuses on the ammonia sensing principle of the metal oxides. It also includes various approaches adopted for increasing the gas sensitivity of metal-oxide sensors. Increasing the sensitivity of the ammonia gas sensor includes size effects and doping by metal or other metal oxides which will change the microstructure and morphology of the metal oxides. Different parameters that affect the performances like sensitivity, stability, and selectivity of gas sensors are discussed in this paper. Performances of the most operated metal oxides with strengths and limitations in ammonia gas sensing application are reviewed. The challenges for the development of high sensitive and selective ammonia gas sensor are also discussed.

scholarly journals Optimization of a Low-Power Chemoresistive Gas Sensor: Predictive Thermal Modelling and Mechanical Failure Analysis

Sensors ◽  
2021 ◽  
Vol 21 (3) ◽  
pp. 783 ◽  
Author(s):  
Andrea Gaiardo ◽  
David Novel ◽  
Elia Scattolo ◽  
Michele Crivellari ◽  
Antonino Picciotto ◽  
...  
Keyword(s):  
Low Power ◽  
Failure Analysis ◽  
Gas Sensors ◽  
High Performance ◽  
Gas Sensing ◽  
Mechanical Failure ◽  
Sensing Applications ◽  
Theoretical Approaches ◽  
Sensing Material ◽  
Silicon Bulk

The substrate plays a key role in chemoresistive gas sensors. It acts as mechanical support for the sensing material, hosts the heating element and, also, aids the sensing material in signal transduction. In recent years, a significant improvement in the substrate production process has been achieved, thanks to the advances in micro- and nanofabrication for micro-electro-mechanical system (MEMS) technologies. In addition, the use of innovative materials and smaller low-power consumption silicon microheaters led to the development of high-performance gas sensors. Various heater layouts were investigated to optimize the temperature distribution on the membrane, and a suspended membrane configuration was exploited to avoid heat loss by conduction through the silicon bulk. However, there is a lack of comprehensive studies focused on predictive models for the optimization of the thermal and mechanical properties of a microheater. In this work, three microheater layouts in three membrane sizes were developed using the microfabrication process. The performance of these devices was evaluated to predict their thermal and mechanical behaviors by using both experimental and theoretical approaches. Finally, a statistical method was employed to cross-correlate the thermal predictive model and the mechanical failure analysis, aiming at microheater design optimization for gas-sensing applications.

scholarly journals Advanced development of metal oxide nanomaterials for H2 gas sensing applications

2021 ◽  
Author(s):  
Yushu Shi ◽  
Huiyan Xu ◽  
Tongyao Liu ◽  
Shah Zeb ◽  
Yong Nie ◽  
...  
Keyword(s):  
Metal Oxide ◽  
Gas Sensors ◽  
Gas Sensing ◽  
The Past ◽  
Sensing Applications ◽  
The Future ◽  
Metal Oxide Nanomaterials ◽  
Nanomaterials Synthesis ◽  
Advanced Development

The scheme of the structure of this review includes an introduction from the metal oxide nanomaterials’ synthesis to application in H2 gas sensors—a vision from the past to the future.

scholarly journals Recent Progress of Toxic Gas Sensors Based on 3D Graphene Frameworks

Sensors ◽  
2021 ◽  
Vol 21 (10) ◽  
pp. 3386
Author(s):  
Qichao Dong ◽  
Min Xiao ◽  
Zengyong Chu ◽  
Guochen Li ◽  
Ye Zhang
Keyword(s):  
Gas Sensors ◽  
Recent Progress ◽  
Limit Of Detection ◽  
3D Structure ◽  
Ammonia Nitrogen ◽  
Gas Sensitivity ◽  
3D Graphene ◽  
Toxic Gases ◽  
Global Issue ◽  
Ppm Level

Air pollution is becoming an increasingly important global issue. Toxic gases such as ammonia, nitrogen dioxide, and volatile organic compounds (VOCs) like phenol are very common air pollutants. To date, various sensing methods have been proposed to detect these toxic gases. Researchers are trying their best to build sensors with the lowest detection limit, the highest sensitivity, and the best selectivity. As a 2D material, graphene is very sensitive to many gases and so can be used for gas sensors. Recent studies have shown that graphene with a 3D structure can increase the gas sensitivity of the sensors. The limit of detection (LOD) of the sensors can be upgraded from ppm level to several ppb level. In this review, the recent progress of the gas sensors based on 3D graphene frameworks in the detection of harmful gases is summarized and discussed.

SnO2 Nano/Microfibers for Gas Sensors

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.

Nanomaterial-based gas sensors used for breath diagnosis

2020 ◽  
Vol 8 (16) ◽  
pp. 3231-3248 ◽  
Author(s):  
Xinyuan Zhou ◽  
Zhenjie Xue ◽  
Xiangyu Chen ◽  
Chuanhui Huang ◽  
Wanqiao Bai ◽  
...  
Keyword(s):  
Physicochemical Properties ◽  
Gas Sensors ◽  
Active Sites ◽  
Gas Sensing ◽  
High Surface ◽  
Volume Ratio ◽  
Sensing Applications ◽  
Enormous Number

Gas-sensing applications commonly use nanomaterials (NMs) because of their unique physicochemical properties, including a high surface-to-volume ratio, enormous number of active sites, controllable morphology, and potential for miniaturisation.

scholarly journals Room-temperature synthesis and CO2-gas sensitivity of bismuth oxide nanosensors

RSC Advances ◽  
2020 ◽  
Vol 10 (29) ◽  
pp. 17217-17227 ◽  
Author(s):  
Pritamkumar V. Shinde ◽  
Nanasaheb M. Shinde ◽  
Shoyebmohamad F. Shaikh ◽  
Damin Lee ◽  
Je Moon Yun ◽  
...  
Keyword(s):  
Carbon Dioxide ◽  
Bismuth Oxide ◽  
Room Temperature ◽  
Gas Sensing ◽  
Deposition Method ◽  
Gas Sensitivity ◽  
Temperature Synthesis ◽  
Co2 Gas ◽  
Surface Areas ◽  
Sensing Applications

Room-temperature (27 °C) synthesis and carbon dioxide (CO2)-gas-sensing applications of bismuth oxide (Bi2O3) nanosensors obtained via a direct and superfast chemical-bath-deposition method (CBD) with different surface areas and structures.

Sign in / Sign up

Export Citation Format

Share Document