Smart sensors based on graphene field effect transistor (GFET) and biological receptors are regarded as a promising nanomaterial that could be the basis for future…
Smart sensors based on graphene field effect transistor (GFET) and biological receptors are regarded as a promising nanomaterial that could be the basis for future generation of low-power, faster, selective real-time monitoring of target analytes and smaller electronics. So, the purpose of this paper is to provide details of sensors based on selective nanocoatings by combining trinitrotoluene (TNT) receptors (Trp-His-Trp) bound to conjugated polydiacetylene polymers on a graphene channel in GFET for detecting explosives TNT.
Following an introduction, this paper describes the way of manufacturing of the GFET sensor by using investigation methods for transferring graphene sheet from Cu foil to target substrates, which is functionalized by the TNT peptide receptors, to offer a system which has the capability of answering the presence of related target molecules (TNT). Finally, brief conclusions are drawn.
In a word, shortly after graphene discovery, it has been explored with a variety of methods gradually. Because of its exceptional electrical properties (e.g. extremely high carrier mobility and capacity), electrochemical properties such as high electron transfer rate and structural properties, graphene has already showed great potential and success in chemical and biological sensing fields. Therefore, the authors used a biological receptor with a field effect transistor (FET) based on graphene to fabricate sensor for achieving high sensitivity and selectivity that can detect explosive substances such as TNT. The transport property changed compared to that of the FET made by intrinsic graphene, that is, the Dirac point position moved from positive Vg to negative Vg, indicating the transition of graphene from p-type to n-type after annealing in TNT, and the results show the bipolar property change of GFET with the TNT concentration and the possibility to develop a robust, easy-to-use and low-cost TNT detection method for performing a sensitive, reliable and semi-quantitative detection in a wide detection range.
In this timeframe of history, TNT is a common explosive used in both military and industrial settings. Its convenient handling properties and explosive strength make it a common choice in military operations and bioterrorism. TNT and other conventional explosives are the mainstays of terrorist bombs and the anti-personnel mines that kill or injure more than 15,000 people annually in war-torn countries. In large, open-air environments, such as airports, train stations and minefields, concentrations of these explosives can be vanishingly small – a few parts of TNT, for instance, per trillion parts of air. That can make it impossible for conventional bomb and mine detectors to detect the explosives and save lives. So, in this paper, the authors report a potential solution with design and manufacture of a GFET sensor based on a biological receptor for real-time detection of TNT explosives specifically.
Miniaturized smart sensors that can perform sensitive and selective real-time monitoring of target analytes are tremendously valuable for various sensing applications. So…
Miniaturized smart sensors that can perform sensitive and selective real-time monitoring of target analytes are tremendously valuable for various sensing applications. So, the purpose of this paper is to provide details of sensors based on selective nanocoatings by combining trinitrotoluene (TNT) receptors bound to conjugated polydiacetylene (PDA) polymers with single-walled carbon nanotube field-effect transistors (CNTFETs) for detecting explosives TNT.
Following an introduction, this paper describes the way of creating an FET with CNTs, which are functionalized by the peptide based on TNT molecule recognition elements and PDA, to offer a system which has the capability of answering the presence of related target molecules (TNT). Finally, brief conclusions are drawn.
Single-wall nanotubes and reduced graphene oxide are interesting materials for creating biosensors of FETs at nanoscale because of unique electrical, mechanical, geometrical and biocompatible properties. Therefore, this sensor is designed and manufactured, and the results of applying TNT to sensor show good sensitivity and selectivity response.
In this timeframe of history, sensors based on CNTFET are required for different uses, including clinical diagnosis technologies, environmental tests and bioterrorism recognition technologies, that correspond to the military conflicts and terrorism. So, CNTFET sensor design provides real-time detection of TNT explosives.
– The purpose of this paper is to demonstrate a successful fabrication of 2 × 128 linear array of typical infrared (IR) detectors made of p-type tSi/porous Si Schottky barrier.
The purpose of this paper is to demonstrate a successful fabrication of 2 × 128 linear array of typical infrared (IR) detectors made of p-type tSi/porous Si Schottky barrier.
Using metal-assisted chemical etching (MaCE) as a unique approach, a sample definition of a porous Si nanostructure region for fabricating of any high-density photodetectors array has been formulated. Besides, the uniformity of pixels at different position along the array has been confirmed by optical images and measurements of photocurrent in IR regime at room temperature.
The experimental result illustrates the existence of an open-circuit voltage up to 30 mV at 1.5-μm wavelength for an area of 50 × 50 μm2. Additionally, this behavior is almost the same at different pixels of fabricated array.
The uniformity of pixels and definition of nanostructure region are two most important challenges in fabrication of any high-density photodetectors array.
MaCE guarantees formation of reproducible, high-fidelity and controllable nanometer-size porous Si with well-defined and sharp edges of the patterned areas.
The proposed method offers a low-cost and simple process to fabricate high-density arrays of Schottky detectors which are compatible with the complementary metal-oxide semiconductor process.