Download or read book Non contact Characterization of Carbon Nanotube Based Strain Sensors Using Millimeter Waves written by Seyda Naz Alasahin and published by . This book was released on 2022 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Carbon nanotubes (CNTs) are unique tubular structures with high thermal and electrical conductivity, distinct optical characteristics, and high mechanical stiffness and strength. Carbon nanotube (CNT) composites have widely been used as strain sensors because of their electrical-mechanical coupling behavior. Typically, these piezoresistive sensors require direct measurement of electrical resistance change using an external source connected with wires. This research introduces a new, non-contact measurement method to detect the change in electrical conductivity of carbon nanotube-based strain sensors using high-frequency millimeter wave technology. By analyzing the transmission coefficient from the textile-based CNT composite, we were able to observe the piezoresistive effect. Sensors were characterized over a broad frequency band, from 82 GHz to 100 GHz, with applied strain up to 40%. Fabrics were coated with a sizing composed of an aqueous dispersion of multi-walled CNTs. Sets of fabrics with different CNT concentration were examined to investigate the sensitivity, polarization effects and isotropy properties of manufactured sensors under three different case studies.
Download or read book Carbon Nanotube Based Sensors written by Anindya Nag and published by CRC Press. This book was released on 2024-05-02 with total page 355 pages. Available in PDF, EPUB and Kindle. Book excerpt: Carbon Nanotube-Based Sensors: Fabrication, Characterization, and Implementation highlights the latest research and developments on carbon nanotubes (CNTs) and their applications in sensors and sensing systems. It offers an overview of CNTs, including their synthesis, functionalization, characterization, and toxicology. It then delves into the fabrication and various applications of CNT-based sensors. FEATURES Defines the significance of different forms of CNT-based sensors synthesized for diverse engineering applications and compares the feasibility of their generation Helps readers evaluate different types of fabrication techniques to generate CNTs and their subsequent sensing Discusses fabrication of low-cost, efficient CNTs-based sensors that can be used for diverse applications and sheds light on synthesis methods for a range of printing techniques Highlights challenges and advances in security-related issues using CNTs-based sensors This book is aimed at researchers in the fields of materials and electrical engineering who are interested in the development of sensor technology for industrial, biomedical, and related applications.
Download or read book Testing and Characterization of Carbon Nanotubes as Strain Sensors written by Juan D. Diaz and published by . This book was released on 2011 with total page 43 pages. Available in PDF, EPUB and Kindle. Book excerpt: The potential of using carbon nanotube coated flexible cloth as strain gauges was studied. Samples were prepared by sonicating strips of cloth inside a 1mg/ml carbon nanotube in propylene carbonate solution. A dynamic mechanical analyzer was built that applied uniaxial cyclical strains to the samples and recorded the force and strain applied. The DMA also provided a constant voltage to the samples while recording the resistance response of the strain gauges. The samples were tested using the dynamic mechanical analyzer for their response to variables such as strain and time. The samples were successfully tested at strains ranging from 1% to 50%. The conductivity of the samples was measured. We studied the effects that a carboxylate and the sulfonate functional groups of the carbon nanotubes have on the strain sensors, the effect of the sonication time, and the effect that leaving the strain sensors inside the solution for different amount of times has on the strain sensors. It was discovered that the samples dried overtime, thus decreasing the conductivity of the samples and damaging the strain sensors. An encapsulation method was developed and studied to counter the drying effect. The results showed that the encapsulation method did delay the decaying of the samples. Moreover, it was concluded that the sulfonate group had higher changes in resistance than the carboxylate group. While increased sonication time did not seem to have a measurable effect on the resistance of the sulfonate CNT samples, this was not true for the carboxylate group CNTs. The carboxylate group CNTs seemed to have a higher initial resistance with longer sonication time and a lower resistance with increasing time sitting in the solution. Overall, it was concluded that carbon nanotubes have a promising potential as macro level strain sensors for high-elongation applications but more development is yet to be done.
Download or read book Synthesis and Characterization of a Carbon Nanotube Based Composite Strain Sensor written by Matthew Clayton Boehle and published by . This book was released on 2016 with total page 68 pages. Available in PDF, EPUB and Kindle. Book excerpt: In order to more effectively monitor the health of composite structures, a fuzzy fiber strain sensor was created. The fuzzy fiber is a bundle of glass fibers with carbon nanotubes or nanofibers grown on the surface using a novel chemical vapor deposition process. The nanotube coating makes the fiber bundle conductive while the small conductive path increases sensitivity. The fuzzy fiber sensor can replace conventional metal foil strain gauges in composite applications. The sensor was first characterized by use of a micro-tension test to generate load vs. resistance plots to demonstrate the feasibility of the sensor. The fibers were then cast into epoxy dogbone specimens to enable testing with an extensometer to quantify its strain sensitivity. Sensors were then embedded in carbon fiber prepreg panels. Specimens were prepared to demonstrate their performance in a composite laminate typical of aerospace structures. A multi-axial specimen was constructed to test sensor response to longitudinal, transverse and off-axis loading cases. Cyclic tests were performed to check for hysteresis or non-reversible changes to the sensor. A finite element model was created to compare the experimental results to the expected behavior based on the Poisson effect.
Download or read book Experimental Characterization and Simulation of Carbon Nanotube Strain Sensing Films written by Nagendra Krishna Chaitanya Tummalapalli and published by . This book was released on 2016 with total page 103 pages. Available in PDF, EPUB and Kindle. Book excerpt: Carbon Nanotubes (CNTs) have excellent mechanical, electrical and electromechanical properties. These properties led to a lot of novel applications. Due to change in electrical properties under mechanical loading, these composites have potential applications in strain sensors, when these are fabricated as films. CNT-based films are commonly fabricated using different physical and chemical techniques based on the property requirements governing those applications. In this work, CNT films were prepared using wet chemical based methods and chemical vapor deposition techniques. Plasma chemical vapor deposition using microwave power is used in the first method to deposit films on silicon substrates, using Nickel film as a catalyst layer. The effect of different processing steps in this method, viz., hydrogen annealing, hydrogen plasma pre-growth treatment and MWCVD deposition properties on the film properties is studied in the first stage. In the second method, Carbon nanotube-polyurethane nanocomposite films of different loading proportions (1 to 8%) are prepared along with N-methyl-2-pyrrolidone (NMP) on different substrates using a spin coating. These film properties were analyzed using different characterization techniques. These studies demonstrated the optimization of the growth and preprocess parameters with respect to the structural phase, microstructure and conductivity of these films in both the methods. Simulation of the CNT sensor characteristics was performed using COMSOL Multiphysics software. Optical lithography is used to fabricate the sensor structures using CNT nanocomposite films. The results of these studies were discussed in detail.
Download or read book Carbon Nanotube Based Sensors written by and published by . This book was released on 2024-05 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: ""Carbon Nanotube-Based Sensors" highlights the latest research and developments on carbon nanotubes (CNTs) and their applications in sensors and sensing systems. It offers an overview of CNTs, including their synthesis, functionalization, characterization, and toxicology. It then delves into the fabrication and various applications of CNT-based sensors. This book is aimed at researchers in the fields of materials and electrical engineering who are interested in the development of sensor technology for industrial, biomedical, and related applications"--
Download or read book Characterization of the Mechanical and Electromechanical Properties of Carbon Nanotube latex Thin Films written by Long Wang and published by . This book was released on 2016 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The safe, reliable, and efficient operation of structural systems can be undermined by various damage modes. To identify and respond to structural damage in a timely fashion, technologies for structural health monitoring (SHM) have been extensively studied and widely applied in practice. In this context, strain sensors play a crucial role in evaluating structural performance, as they can provide insights about internal stresses within structural components. As compared to conventional rigid and locally implemented strain sensors, piezoresistive nanostructured materials provide considerable opportunities for developing flexible, light-weight, and densely distributed sensors or “sensing skins.” Although many types of nanomaterial-based strain sensors have been fabricated, most of them rely on complicated and expensive manufacturing procedures, which hinder their large-scale applications. To address the aforementioned limitations, this thesis proposes the development, optimization, and characterization of a type of spray-fabricated carbon nanotube (CNT)-based thin film strain sensor. By using spray coating or airbrushing, thin films can be coated and readily applied onto large structural surfaces. It was found that the mechanical and electrical properties of the nanocomposite films could be optimized by modifying CNT concentrations and conducting post-fabrication annealing. Overall, the CNT nanocomposite films possess favorable mechanical properties as well as stable and reversible electromechanical properties, rendering them promising candidates as strain sensors suitable for SHM applications.
Download or read book Quantum Transport Characteristics of Tuned Mesoscopic Devices written by Ahmed Elseddawy and published by LAP Lambert Academic Publishing. This book was released on 2013 with total page 100 pages. Available in PDF, EPUB and Kindle. Book excerpt: Nanoelectromechanical systems (NEMS) in which a nanomechanical resonator is coupled to a mesoscopic conductor, such as a single-electron transistor, form a new class of mesoscopic quantum systems in which there is a fascinating interplay between the electrical and mechanical degree of freedom. Coupling to nanomechanical degrees of freedom can modify the transport properties of mesoscopic conductors substantially, giving rise to a number of novel phenomena such as electron shuttling effects. Sensors continue to make significant impact in everyday life. With the advent of nanotechnology, research is underway to create miniaturized sensors. The application of carbon nanotubes in next-generation of sensors has the potential of revolutionizing the sensor industry due to their inherent properties such as small size, high strength, high electrical and thermal conductivity, and high specific surface area. Carbon nanotubes which are modeled under axial strain and torsion have predictable chirality dependent band gap changes in response to strain. The present thesis shows how we use carbon nanotub-based NEMS resonators as bio-molecules detection and also as strain sensor.
Download or read book Characterization of Carbon Nanotubes Based Resistive and Capacitive Gas Sensors written by Ning Ma and published by . This book was released on 2007 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Printed Flexible Sensors written by Anindya Nag and published by Springer. This book was released on 2019-03-11 with total page 205 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book presents recent advances in the design, fabrication and implementation of flexible printed sensors. It explores a range of materials for developing the electrode and substrate parts of the sensors, on the basis of their electrical and mechanical characteristics. The sensors were processed using laser cutting and 3D printing techniques, and the sensors developed were employed in a number of healthcare, environmental and industrial applications, including: monitoring of physiological movements, respiration, salinity and nitrate measurement, and tactile sensing. The type of sensor selected for each application depended on its dimensions, robustness and sensitivity. The sensors fabricated were also embedded in an IoT-based system, allowing them to be integrated into real-time applications.
Download or read book Carbon Nanotube Electronics written by Ali Javey and published by Springer Science & Business Media. This book was released on 2009-04-21 with total page 275 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book provides a complete overview of the field of carbon nanotube electronics. It covers materials and physical properties, synthesis and fabrication processes, devices and circuits, modeling, and finally novel applications of nanotube-based electronics. The book introduces fundamental device physics and circuit concepts of 1-D electronics. At the same time it provides specific examples of the state-of-the-art nanotube devices.
Download or read book Carbon Nanotube based Optical Sensors for Pharmaceutical Applications written by Daniel Parker Salem and published by . This book was released on 2019 with total page 221 pages. Available in PDF, EPUB and Kindle. Book excerpt: Semiconducting single-walled carbon nanotubes (SWCNTs) are attractive transducers for biosensor applications due to their unique photostability, single molecule sensitivity, and ease of multiplexing. Sensors can be rendered selective via several detection modalities including the use of natural recognition elements (e.g., proteins) as well as the formation of synthetic molecular recognition sites from adsorbed heteropolymers. However, to date, deployment of SWCNT-based biosensors has been limited. The aim of this thesis was to study the design and development of SWCNT-based optical sensors for analytes relevant to the food and pharmaceutical industries including neurotransmitters, proteins, and metal ions. The research described in this thesis spans several levels of nanosensor development including: i) the fundamental study of SWCNT-polymer interactions and their dependence on solution properties; ii) sensor development using existing detection modalities and the use of mathematical modeling to guide sensor design and interpret data; and iii) the invention of a new sensor form factor enabling long-term sensor stability and point-of-use measurements. Our fundamental work on SWCNT-polymer interactions investigates the influence of polymer structure, SWCNT structure, and solution properties on molecular recognition, using single-stranded DNA as a model polymer system. We find that specific ssDNA sequences are able to form distinct corona phases across SWCNT chiralities, resulting in varying response characteristics to a panel of biomolecule probe analytes. In addition, we find that ssDNA-SWCNT fluorescence and wrapping structure is significantly influenced by the solution ionic strength, pH, and dissolved oxygen in a sequence-dependent manner. We are able to model this phenomenon and demonstrate the implications of solution conditions on molecular recognition, modulating the recognition of riboflavin. These results provide insight into the unique molecular interactions between DNA and the SWCNT surface, and have implications for molecular sensing, assembly, and nanoparticle separations. In addition to our experimental work, we used mathematical modeling to guide sensor design for biopharmaceutical characterization. A mathematical formulation for glycoprotein characterization was developed as well as a dynamic kinetic model to describe the data output by a label-free array of non-selective glycan sensors. We use the formulated model to guide microarray design by answering questions regarding the number and type of sensors needed to quantitatively characterize a glycoprotein mixture. As a second example, we report the design of a novel, diffusion-based assay for the characterization of protein aggregation. Specifically, we design hydrogel-encapsulated SWCNT sensors with a tunable hydrogel layer to influence the diffusion of immunoglobulin G protein species of variable size, and we develop a combined model that describes both the diffusion of analyte and analyte-sensor binding. By measuring the sensor response to a series of well-characterized protein standards that have undergone varying levels of UV stress, we demonstrate the ability to detect protein aggregates at a concentration as low as one percent on a molar basis. Finally, we report the development of a new form factor for optical nanosensor deployment involving the immobilization of SWCNT sensors onto paper substrates. We find that SWCNT optical sensors can be immobilized onto many different paper materials without influencing sensor performance. Moreover, we pattern hydrophobic barriers onto the paper substrates to create 1-dimensional sensor arrays, or barcodes, that are used for rapid, multiplexed characterization of several metal ions including Pb(II), Cd(II) and Hg(II). In addition to providing a new form factor for conducting point-of-use sensor measurements, these findings have the potential to significantly enhance the functionality of SWCNT-based optical sensors by interfacing them with existing paper diagnostic technologies including the manipulation of fluid flow, chemical reaction, and separation.
Download or read book Characterization of Multifunctional Carbon Nanotube Yarns written by Christian David Page and published by . This book was released on 2013 with total page 92 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Synthesis Characterization and Utility of Carbon Nanotube Based Hybrid Sensors in Bioanalytical Applications written by Sushmee Badhulika and published by . This book was released on 2011 with total page 120 pages. Available in PDF, EPUB and Kindle. Book excerpt: The detection of gaseous analytes and biological molecules is of prime importance in the fields of environmental pollution control, food and water - safety and analysis; and medical diagnostics. This necessitates the development of advanced and improved technology that is reliable, inexpensive and suitable for high volume production. The conventional sensors are often thin film based which lack sensitivity due to the phenomena of current shunting across the charge depleted region when an analyte binds with them. One dimensional (1-D) nanostructures provide a better alternative for sensing applications by eliminating the issue of current shunting due to their 1-D geometries and facilitating device miniaturization and low power operations. Carbon nanotubes (CNTs) are 1-D nanostructures that possess small size, high mechanical strength, high electrical and thermal conductivity and high specific area that have resulted in their wide spread applications in sensor technology. To overcome the issue of low sensitivity of pristine CNTs and to widen their scope, hybrid devices have been fabricated that combine the synergistic properties of CNTs along with materials like metals and conducting polymers (CPs). CPs exhibit electronic, magnetic and optical properties of metals and semiconductors while retaining the processing advantages of polymers. Their high chemical sensitivity, room temperature operation and tunable charge transport properties has made them ideal for use as transducing elements in chemical sensors. In this dissertation, various CNT based hybrid devices such as CNT-conducting polymer and graphene-CNT-metal nanoparticles based sensors have been developed and demonstrated towards bioanalytical applications such as detection of volatile organic compounds (VOCs) and saccharides. Electrochemical polymerization enabled the synthesis of CPs and metal nanoparticles in a simple, cost effective and controlled way on the surface of CNT based platforms thus resulting in the fabrication of hybrid sensors which exhibited superior properties and improved performance when used for sensing applications using various modes of sensor configurations.
Download or read book Manufacturing and Characterization of Printed Strain Gauges Based on Carbon Nanotubes written by Andrea Arreba Garcia-Abad and published by . This book was released on 2010 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Nanotubes and Nanofibers written by Yury Gogotsi and published by CRC Press. This book was released on 2019-08-30 with total page 264 pages. Available in PDF, EPUB and Kindle. Book excerpt: Size, Shape, and Synthesis Key to "Tuning" Properties The discovery and rapid evolution of carbon nanotubes have led to a vastly improved understanding of nanotechnology, as well as dozens of possible applications for nanomaterials of different shapes and sizes ranging from composites to biology, medicine, energy, transportation, and electronic devices. Nanotubes and Nanofibers offers an overview of structure-property relationships, synthesis and purification, and potential applications of carbon nanotubes and fibers, including whiskers, cones, nanobelts, and nanowires. Using research on carbon nanotubes as a foundation to further developments, this book discusses methods for growing and synthesizing amorphous and nanocrystalline graphitic carbon structures and inorganic nanomaterials, including wet chemical synthesis, chemical vapor deposition (CVD), arc discharge, and others. It also describes boron nitride and metal chalcogenide nanotubes in detail and reviews the unique properties and methods for characterizing and producing single-crystalline semiconducting and functional-oxide nanowires. The chapters also identify challenges involving the controlled growth, processing, and assembly of organic and inorganic nanostructures that must be addressed before large-scale applications can be implemented. Edited by award-winning professor and researcher Dr. Yury Gogotsi, Nanotubes and Nanofibers offers a well-rounded perspective on the advances leading to improved nanomaterial properties for a range of new devices and applications including electronic devices, structural composites, hydrogen and gas storage, electrodes in electrochemical energy-storage systems, sorbents, and filters.
Download or read book Development and Characterization of Carbon Nanotubes for Sensor Applications written by Jessica Eileen Otto and published by . This book was released on 2005 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Fourier Transform Infrared Spectroscopy (FTIR) was used to verify the attachment of both the carboxyl group COOH and LOX to the respective carbon nanotubes samples. Scanning electron microscopy (SEM) was used to analyze the carbon nanotube lactate electrode sample to examine the structure of the electrode. Both pH and lactate biosensors were used in a standard three electrode electrochemical cell where the carbon nanotubes behaved as the working electrode with an Ag/AgCl reference electrode and a platinum wire as the counter electrode. Each sample was separately interrogated by several voltammetry techniques such as linear, cyclic, and square wave. Square wave voltammetry proved to be the best template to use to sense the target analytes. The functionalized CNT-COOH electrode displayed a linear response to pH 1-10, with a negative voltage shift corresponding to an increase in pH.
