scholarly journals A Room-Temperature CNT/Fe3O4 Based Passive Wireless Gas Sensor

Sensors ◽  
2018 ◽  
Vol 18 (10) ◽  
pp. 3542 ◽  
Author(s):  
Tao Guo ◽  
Tianhao Zhou ◽  
Qiulin Tan ◽  
Qianqian Guo ◽  
Fengxiang Lu ◽  
...  
Keyword(s):  
Carbon Nanotube ◽  
Gas Sensor ◽  
Room Temperature ◽  
Gas Sensing ◽  
Low Cost ◽  
Fast Response ◽  
Sensing Material ◽  
Recovery Times ◽  
Response And Recovery ◽  
Good Repeatability

A carbon nanotube/Fe3O4 thin film-based wireless passive gas sensor with better performance is proposed. The sensitive test mechanism of LC (Inductance and capacitance resonant) wireless sensors is analyzed and the reason for choosing Fe3O4 as a gas sensing material is explained. The design and fabrication process of the sensor and the testing method are introduced. Experimental results reveal that the proposed carbon nanotube (CNT)/Fe3O4 based sensor performs well on sensing ammonia (NH3) at room temperature. The sensor exhibits not only an excellent response, good selectivity, and fast response and recovery times at room temperature, but is also characterized by good repeatability and low cost. The results for the wireless gas sensor’s performance for different NH3 gas concentrations are presented. The developed device is promising for the establishment of wireless gas sensors in harsh environments.

Enhanced Gas Sensing of Tin Dioxide Based Sensor for Indoor Formaldehyde Application

2021 ◽  
Vol 16 (2) ◽  
pp. 337-342
Author(s):  
Gaoqi Zhang ◽  
Fan Zhang ◽  
Kaifang Wang ◽  
Shanyu Liu ◽  
Ying Wang ◽  
...  
Keyword(s):  
Gas Sensors ◽  
Tin Dioxide ◽  
Gas Sensing ◽  
Fast Response ◽  
Sensing Material ◽  
Gas Sensing Properties ◽  
Recovery Times ◽  
Response And Recovery ◽  
Formaldehyde Sensing ◽  
Gas Response

Indoor formaldehyde detection is of great important at present. Using efficient solvothermal method, nanosheet-constructed and nanorod-constructed hierarchical tin dioxide (SnO2) microspheres were successfully synthesized in this work and used for the gas sensing material for indoor formaldehyde application. The as-prepared two kinds of SnO2 gas sensing materials were applied to fabricate the gas sensors and formaldehyde gas sensing experiments were carried out. The HCHO gas sensing tests indicate that the gas response of the nanosheet-constructed SnO2 microspheres is about 1.7 times higher than that of the nanorod-constructed SnO2 microspheres. In addition, both of the two SnO2 based gas sensors show almost fast response and recovery time to HCHO gas. For the nanosheet-constructed microspheres, the response value is estimated to be 32.0 at 350 °C to 60 ppm formaldehyde gas, while the response and recovery times are 7 and 5 s, respectively. The simple and efficient preparation method and improved gas sensing properties show that the as-synthesized hierarchical SnO2 microsphere that is constructed by a large amount of nanosheets exhibits significant potential application for the indoor formaldehyde sensing.

scholarly journals Hexanal Gas Detection Using Chitosan Biopolymer as Sensing Material at Room Temperature

2016 ◽  
Vol 2016 ◽  
pp. 1-7 ◽  
Author(s):  
Devi Shantini ◽  
Irwana Nainggolan ◽  
Tulus Ikhsan Nasution ◽  
Mohd Nazree Derman ◽  
Roshida Mustaffa ◽  
...  
Keyword(s):  
Dairy Products ◽  
Room Temperature ◽  
Gas Sensing ◽  
Low Cost ◽  
Chitosan Film ◽  
Gas Detection ◽  
Film Sensor ◽  
Sensing Material ◽  
Good Repeatability ◽  
Chitosan Biopolymer

Hexanal was identified as one of the major volatile gases which are produced in degraded dairy products and wood industries. Therefore, preliminary study on hexanal gas detection with the laboratory scale was carried out in this paper. Electrical testing with chitosan as a sensing material to sense hexanal gas in low concentration was carried out at room temperature. Chitosan sensor was fabricated by using electrochemical deposition technique to form active sensing layer. The response of the chitosan film sensor (CFS) towards hexanal was tested via electrical testing by exposing different hexanal concentrations ranging between 20 ppm, 100 ppm, 200 ppm, and 300 ppm using air as a carrier gas. Sensing properties of the CFS toward hexanal exposure including responsibility, recovery, repeatability, stability, and selectively were studied. Overall, our result suggested that hexanal sensor based on chitosan was able to perform well at room temperature demonstrated by good response, good recovery, good repeatability, good stability, and good selectively. This simple and low cost sensor has high potential to be utilized in early quality degradation detection in dairy products and can be used to monitor the level of hexanal exposure in wood industries.

scholarly journals A Novel Type Room Temperature Surface Photovoltage Gas Sensor Device

Sensors ◽  
2018 ◽  
Vol 18 (9) ◽  
pp. 2919 ◽  
Author(s):  
Monika Kwoka ◽  
Michal Borysiewicz ◽  
Pawel Tomkiewicz ◽  
Anna Piotrowska ◽  
Jacek Szuber
Keyword(s):  
Gas Sensor ◽  
Room Temperature ◽  
Gas Sensing ◽  
Signal To Noise Ratio ◽  
Fast Response ◽  
Surface Photovoltage ◽  
Kelvin Probe ◽  
Sensor Device ◽  
Sensing Material ◽  
Highly Sensitive

In this paper a novel type of a highly sensitive gas sensor device based on the surface photovoltage effect is described. It is based on the Kelvin probe approach. Porous ZnO nanostructured thin films deposited by the direct current (DC) reactive magnetron sputtering method are used as the active gas sensing electrode material. Crucially, the obtained gas sensing material exhibited a nanocoral surface morphology and surface Zn to O non-stoichiometry with respect to its bulk mass. Among other responses, the demonstrated SPV gas sensor device exhibits a high response to an NO2 concentration as low as 1 ppm, with a signal to noise ratio of about 50 and a fast response time of several seconds under room temperature conditions.

Zinc Oxide/Reduced Graphene Oxide Nanocomposites for Rapid Detection of Toluene Gas at Room Temperature

2020 ◽  
Vol 18 (10) ◽  
pp. 745-749
Author(s):  
Chih-Chia Wang ◽  
Chiu-Hung Liu ◽  
Hsuan-Hua Hsieh ◽  
Chih-Wei Tang ◽  
Chen-Bin Wang
Keyword(s):  
Zinc Oxide ◽  
Graphene Oxide ◽  
Reduced Graphene Oxide ◽  
Room Temperature ◽  
Gas Sensing ◽  
Fast Response ◽  
Reduced Graphene ◽  
New Strategy ◽  
Recovery Times ◽  
Response And Recovery

In this study, a nanostructured zinc oxide/reduced graphene oxide (ZnO/rGO) composite was deposited on a quartz crystal microbalance (QCM) as a toluene gas sensor at room temperature. A series of ZnO, rGO and ZnO/rGO sensing materials was fabricated and characterized by X-ray diffraction (XRD), scanning electron microscope (SEM), and Raman spectroscopy. There was significant efficiency of the ZnO/rGO composite on the sensing performance for toluene. For specific gas fluxes, the nanostructured ZnO/rGO offered sufficient paths and region for vapor diffusion and adsorption. The sensing test results illustrated that the nanostructured ZnO/rGO composite showed significant enhancement in the frequency shifts (△f) for toluene comparing to pure ZnO and rGO. Also, the ZnO/rGO-coated QCM sensor displayed a fast response (both the response and recovery times < 30 s) and reproducibility for sensing toluene gas at room temperature. We believe that the novel insights on ambient temperature gas sensing on nanostructured ZnO/rGO composite could provide a new strategy for preparing a highly efficient sensing materials.

Carbon Nanotube Gas Sensor Fabricated on Anodic Aluminum Oxide

2007 ◽  
Vol 124-126 ◽  
pp. 1309-1312
Author(s):  
Nguyen Duc Hoa ◽  
Nguyen Van Quy ◽  
Gyu Seok Choi ◽  
You Suk Cho ◽  
Se Young Jeong ◽  
...  
Keyword(s):  
Carbon Nanotubes ◽  
Carbon Nanotube ◽  
Gas Sensor ◽  
Chemical Vapor ◽  
Fast Response ◽  
Device Fabrication ◽  
Alumina Oxide ◽  
Response And Recovery ◽  
New Type ◽  
P Type

A new type of gas sensor was realized by directly depositing carbon nanotube on nano channels of the anodic alumina oxide (AAO) fabricated on p-type silicon substrate. The carbon nanotubes were synthesized by thermal chemical vapor deposition at a very high temperature of 1200 oC to improve the crystallinity. The device fabrication process was also developed. The contact of carbon nanotubes and p-type Si substrate showed a Schottky behavior, and the Schottky barrier height increased with exposure to gases while the overall conductivity decreased. The sensors showed fast response and recovery to ammonia gas upon the filling (400 mTorr) and evacuation.

scholarly journals A Novel Type Room Temperature Surface Photovoltage Gas Sensor Device 

2018 ◽  
Author(s):  
Monika Kwoka ◽  
Michal A. Borysiewicz ◽  
Pawel Tomkiewicz ◽  
Anna Piotrowska ◽  
Jacek Szuber
Keyword(s):  
Gas Sensor ◽  
Room Temperature ◽  
Gas Sensing ◽  
Signal To Noise Ratio ◽  
High Sensitivity ◽  
Fast Response ◽  
Surface Photovoltage ◽  
Kelvin Probe ◽  
Sensor Device ◽  
Developed Surface

In this paper a novel type of a highly sensitive gas sensor device based on the surface photovoltage effect is described. The developed surface photovoltage gas sensor is based on a reverse Kelvin probe approach. As the active gas sensing electrode the porous ZnO nanostructured thin films are used deposited by the direct current (DC) reactive magnetron sputtering method exhibiting the nanocoral surface morphology combined with an evident surface nonstoichiometry related to the unintentional surface carbon and water vapor contaminations. Among others, the demonstrated SPV gas sensor device exhibits a high sensitivity of 1 ppm to NO2 with a signal to noise ratio of about 50 and a fast response time of several seconds under the room temperature conditions.

Gas Sensing Properties of Porous ZnO Nano-Platelet Films

2007 ◽  
Vol 1035 ◽  
Author(s):  
Amandeep Saluja ◽  
Jie Pan ◽  
Lei Kerr ◽  
Eunjung Cho ◽  
Seth Hubbard
Keyword(s):  
Gas Flow ◽  
Room Temperature ◽  
Gas Sensing ◽  
Electrode Spacing ◽  
Porous Films ◽  
Gas Sensitivity ◽  
Gas Sensing Properties ◽  
Recovery Times ◽  
Response And Recovery ◽  
Carrier Gas Flow

AbstractIn this work, various ZnO nanostructures were synthesized and a detailed study on the effect of different process parameters such as temperature, carrier gas flow, inter-electrode spacing, gas concentration and material properties on gas sensitivity was conducted. Initial ZnO nanoparticles were prepared by a simple solution chemical process and characterized by Secondary Electron Microscopy (SEM) and Brunauer, Emmet and Teller (BET) Sorptometer to demonstrate the morphology and surface area respectively. Sensitivity of nano-platelets and porous films was measured for different concentrations of the analytes (H2, CO). High response was observed at room temperature for H2 gas with sensitivities in excess 80% for 60ppm and about 55% for 80ppm of H2 gas at room temperature were observed for the nano-platelets and the porous films respectively with short response and recovery times of about 200 seconds. The sensitivity of the nano-platelets to CO gas was also measured and found to be about near 90% for 80 ppm CO at operating temperatures of 200 °C.

Improved gas sensing properties of silver-functionalized ZnSnO3 hollow nanocubes

2018 ◽  
Vol 5 (9) ◽  
pp. 2123-2131 ◽  
Author(s):  
YanYang Yin ◽  
Feng Li ◽  
Nan Zhang ◽  
Shengping Ruan ◽  
Haifeng Zhang ◽  
...  
Keyword(s):  
Gas Sensor ◽  
Gas Sensing ◽  
Fast Response ◽  
Sensing Properties ◽  
Gas Sensing Properties ◽  
Response And Recovery ◽  
Porous Silver ◽  
Acetone Detection

Porous silver-functionalized ZnSnO3 hollow nanocubes as a gas sensor with an ultra-fast response and recovery speed for acetone detection.

Using Palladium Nanocubes on ZnO Nanostructures in Hydrogen Gas Sensor for Fast Response and Recovery Time

2021 ◽  
Vol 21 (4) ◽  
pp. 2495-2499
Author(s):  
Hoang Si Hong ◽  
Tran Vinh Hoang
Keyword(s):  
Gas Sensor ◽  
Recovery Time ◽  
Fast Response ◽  
Hydrogen Gas ◽  
Zno Nanostructures ◽  
Response Recovery ◽  
Sensor Structure ◽  
Recovery Times ◽  
Response And Recovery ◽  
Robust Sensing

We developed a novel sensor structure by synthesizing Pd nanocubes (NCs) decorated on ZnO nanostructures (NSs) applied to resistive-type H2 gas sensor with micro-length in sensing channel. The ZnO NSs were selectively grown between micro-size finger-like interdigital electrodes through microelectromechanical technology. The novel H2 sensor structure with the sensing channel was reduced to micro-size by this proposed method to obtain a sensor with fast response/recovery time. The as-prepared structure exhibited robust sensing performance with a response of 11% at optimal temperature of 150 °C, good linearity, and fast response/recovery time within 10 s. The speed of chemisorption through the diffusion pathway in Pd NCs combined with micro-length in sensing channel in sensor showed fast response and recovery times of 9 and 15 s, respectively, toward 10,000 ppm (1%) H2 at 150 °C. The result showed approximate linearity response in H2 concentration range of 5÷10,000 ppm and a large operating temperature range from room temperature to 200 °C.

The fabrication and gas sensing application of a fast-responding m-CP-PVP composite film/potassium ion-exchanged glass optical waveguide

2017 ◽  
Vol 9 (37) ◽  
pp. 5494-5501 ◽  
Author(s):  
Min Zhu ◽  
Nuerguli Kari ◽  
Yin Yan ◽  
Abliz Yimit
Keyword(s):  
Composite Film ◽  
Optical Waveguide ◽  
Room Temperature ◽  
Gas Sensing ◽  
Potassium Ion ◽  
Recovery Times ◽  
Response And Recovery ◽  
Sensing Application

A simply designed sensor was able to measure trimethylamine (TMA) gas down to a concentration of 0.1 ppb at room temperature, and its response and recovery times were 1.4 s and 5.6 s, respectively.

Sign in / Sign up

Export Citation Format

Share Document