scholarly journals 3.1.2 Chirality-Selective Fabrication of Carbon Nanotube Gas sensor Using Spin-Column Chromatography and Dielectrophoresis

2012 ◽  
Author(s):  
J. Suehiro ◽  
M. Fujioka ◽  
H. Watanabe ◽  
H. Komure ◽  
M. Nakano
2013 ◽  
Vol 699 ◽  
pp. 915-920
Author(s):  
Hideaki Watanabe ◽  
Hiroki Komure ◽  
Michihiko Nakano ◽  
Junya Suehiro

Single-walled carbon nanotubes (SWCNTs) gas sensor has attracted a great deal of attention because of their remarkable properties. The sensor response is attribute to the semiconducting CNT whose electronic properties depend on its chirality. The authors have previously found that the sensor response increased by using separated semiconducting SWCNTs from a mixture with metallic one. Since the electronic structure (metallic or semiconducting) of CNTs is governed by their chirality, a chirality-selective fabrication of CNT gas sensor is essential to improve their performance. In this study, we proposed chirality-based separation of semiconducting SWCNTs by using spin-column chromatography. Pristine CNT suspension was separated into three fractions that had different chiralities of semiconducting SWCNTs. Separated semiconducting CNTs of each fraction were used for fabrication of three CNT gas sensors by dielectrophoresis. Comparison of these sensor responses to NO2 revealed that sensor response depended on the chirality.


2007 ◽  
Vol 124-126 ◽  
pp. 1309-1312
Author(s):  
Nguyen Duc Hoa ◽  
Nguyen Van Quy ◽  
Gyu Seok Choi ◽  
You Suk Cho ◽  
Se Young Jeong ◽  
...  

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.


2021 ◽  
Author(s):  
Salomé Forel ◽  
Leandro Sacco ◽  
Alice Castan ◽  
Ileana Florea ◽  
Costel Sorin Cojocaru

We design a gas sensor by combining two SWCNT-FET devices in an inverter configuration enabling a better system miniaturization together with a reduction of power consumption and ease of data processing.


2011 ◽  
Vol 36 (3) ◽  
pp. 455-458 ◽  
Author(s):  
Hiroharu Kawasaki ◽  
Takeru Kanazawa ◽  
Shin-ichi Aoqui ◽  
Ikuya Muramoto ◽  
Tamiko Ohshima ◽  
...  
Keyword(s):  

2018 ◽  
Vol 30 (1) ◽  
pp. 147-158 ◽  
Author(s):  
K. Kaviyarasu ◽  
Genene T. Mola ◽  
S. O. Oseni ◽  
K. Kanimozhi ◽  
C. Maria Magdalane ◽  
...  

Author(s):  
Taajza Singleton ◽  
Lawrence Kulinsky

Abstract Carbon nanotubes (CNTs) have been implemented in the creation of many micro- and nano-devices due to their physical properties such as large volume-to-surface area as well as their high thermal and electrical conductivity. The paper describes a novel dielectrophoretic step-wise deposition of CNTs (that alternates deposition of CNTs and drying steps) between the interdigitated fingers of carbon electrodes. Multiphysics simulation illustrates the physics of CNT alignment along the electrical field lines that forms a basis for dielectrophoretic deposition of CNTs. This fabrication methodology resulted in the creation of a proof-of-concept nitrogen gas sensor.


2020 ◽  
Vol 20 (7) ◽  
pp. 4011-4014 ◽  
Author(s):  
Maeum Han ◽  
Jae Keon Kim ◽  
Junyeop Lee ◽  
Hee Kyung An ◽  
Jong Pil Yun ◽  
...  

The proposed study describes the development of a carbon nanotube (CNT)-based gas sensor capable of detecting the presence of hydrogen (H2) gas at room temperature. CNT yarn used in the proposed sensor was fabricated from synthesized CNT arrays. Subsequently, the yarn was treated by means of a simple one-step procedure, called acid treatment, to facilitate removal of impurities from the yarn surface and forming functional species. To verify the proposed sensor’s effectiveness with regard to detection of H2 gas at room temperature, acid-treated CNT and pure yarns were fabricated and tested under identical conditions. Corresponding results demonstrate that compared to the untreated CNT yarn, the acid-treated CNT yarn exhibits higher sensitivity to the presence of H2 gas at room temperature. Additionally, the acid-treated CNT yarn was observed to demonstrate excellent selectivity pertaining to H2 gas.


Sign in / Sign up

Export Citation Format

Share Document