Download or read book An In situ Study of Organic Semiconductor Thin Films for Gas Sensing written by and published by . This book was released on 2008 with total page 227 pages. Available in PDF, EPUB and Kindle. Book excerpt: Organic semiconductors are an attractive platform for developing chemisensors, because of their customizable surface chemistry. An understanding of the sensing mechanism would help develop surface chemistry design for molecular recognition. We have studied the steric and chemical effects of acetone and ethanol on sublimated and spun organic films, which are used as chemisensor transducers. We designed deposition and exposure systems to study the surface current and chemistry of rubrene, pentacene, and 5,5'-bis(4-hydroxyhexylphenyl)-2,2'-bithiophene (C6) in response to acetone and ethanol vapors. A rubrene crystal and spun film, as well as sublimated C6 and pentacene films and transistors were exposed under vacuum to saturated vapor pressure acetone gas. The surface current was recorded in real-time, while the infrared absorption (IRAS) signature of the acetone film effect was recorded in-situ. Some chemical interaction between acetone and the organic substrate was observed, and led to the use of saturated alkyl perfluorinated trichlorosilane (FTS) monolayer coverage of rubrene to prevent acetone degradation and removal of an amorphous spun rubrene film. Acetone removed only 1.5% of the FTS film from saturated coverage, physisorbed multilayers of FTS on rubrene. Besides this small chemical effect, the main effect on the sensor current is due to the physisorption of acetone itself. In the cases of pentacene and C6 sublimated films, the surface chemistry and surface current could both be measured on the same film. Acetone intercalation into pentacene and C6 sublimated films perturbed the out-of-plane C-H bending, possibly due to steric interaction. An irreversible reduction in surface current and carrier mobility was found. Acetone caused the thickest pentacene thin film tested (1500 Å) to produce the highest intensity differential peaks, similar to the effect of cooling the film by 3°C - 7°C. However, cooling did not fully account for transistor current reduction. Also, the surface chemistry response decreased upon reuse, and the surface current was not quantitatively reproducible. This behavior may be explained by the fact that the contact adhesive was soluble in acetone. Less surface chemical change occurred for ethanol than for acetone exposures, despite the fact that the C6 molecule has a more reactive hydroxy-hexanol termination.
Download or read book Semiconducting Metal Oxides for Gas Sensing written by Yonghui Deng and published by Springer Nature. This book was released on 2023-08-23 with total page 402 pages. Available in PDF, EPUB and Kindle. Book excerpt: The second edition of this book focuses on the synthesis, design, and application of semiconducting metal oxides as gas sensing materials, including the gas sensing mechanism, and modification methods for sensing materials, while also providing a comprehensive introduction to semiconductor gas sensing devices. As an essential part of IoT (Internet of things), gas sensors have shown great significance and promising prospects. Therefore, studies on functional mesoporous metal oxides, one of the most important gas sensing materials based on their unique Knudsen diffusion behavior and tailored pore structure, have increasingly attracted attention from various disciplines. The book offers a valuable reference guide to metal oxide gas sensing materials for undergraduate and graduate students alike. It will also benefit all researchers who are involved in synthesis and gas sensing of metal oxides nanomaterials with relevant frontier theories and concepts. Engineers working on research and development of semiconductor gas sensors will also find some new ideas for sensor design.
Download or read book Semiconductor Gas Sensors written by Raivo Jaaniso and published by Woodhead Publishing. This book was released on 2019-09-24 with total page 512 pages. Available in PDF, EPUB and Kindle. Book excerpt: Semiconductor Gas Sensors, Second Edition, summarizes recent research on basic principles, new materials and emerging technologies in this essential field. Chapters cover the foundation of the underlying principles and sensing mechanisms of gas sensors, include expanded content on gas sensing characteristics, such as response, sensitivity and cross-sensitivity, present an overview of the nanomaterials utilized for gas sensing, and review the latest applications for semiconductor gas sensors, including environmental monitoring, indoor monitoring, medical applications, CMOS integration and chemical warfare agents. This second edition has been completely updated, thus ensuring it reflects current literature and the latest materials systems and applications. - Includes an overview of key applications, with new chapters on indoor monitoring and medical applications - Reviews developments in gas sensors and sensing methods, including an expanded section on gas sensor theory - Discusses the use of nanomaterials in gas sensing, with new chapters on single-layer graphene sensors, graphene oxide sensors, printed sensors, and much more
Download or read book Organic Thin film Transistor Based Gas Sensors for Putrescine Detection written by Jiaxin Zhu and published by . This book was released on 2018 with total page 96 pages. Available in PDF, EPUB and Kindle. Book excerpt: The application of organic thin film transistors (OTFTs) has been progressing in the area of sensors for decades now. For accomplishing gas sensing in ambient conditions, polymers with good air stability and high enough mobility to detect environmental variations by analytes exposure are required for the OTFT-sensors. In this work, putrescine (PUT) was selected as our primary analyte, as it has high volatility and can be emitted by decayed food products. OTFT-based sensors were made with various polymers as semiconductors to detect PUT vapor. Based on the preliminary study of gas sensing with bottom-gate, bottom-contact (BGBC) OTFTs, a gas sensing system was established with OTFT-sensors, an analyte injection platform and a signal analyzing system, which is presented in Chapter 3. Before and after gas detection, all OTFT devices were characterized by their charge carrier mobility, threshold voltage and current on/off ratio in the glovebox and in air. Additional tests on polymer films were conducted by morphology and crystallinity tests with AFM and XRD. Chapter 4 and Chapter 5 show the screening of polymers as the semiconductor in OTFT sensors. P-type polymers and n-type polymers including commercially available ones and those synthesized by our group were employed in OTFT-sensors. P3HT and N2200 as typical p-type and n-type representatives have succeeded in the detection of PUT vapor as OTFT sensors. In addition, p-type polymers with FTPDO, DPP, indigo and bithiazole cores, n-type polymers with IBDF building block also showed sensing ability towards PUT vapor as OTFT sensors. Chapter 5 especially focuses on a series of 1,4-DPP polymers that exhibited high transistor performance as well as good air stability. As main factors that determine the performance of a sensor, operational temperature, stability, response and recovery time, sensitivity and selectivity of these DPP-polymer sensors showed very promising potential in PUT vapor detection. Food spoilage detection was realized with three types of DPP-sensors to detect vapors emitted by food samples. Mechanism of DPP-sensors to detect PUT vapor was studied by responses of the sensor, IV characteristics of the device, and morphology/crystallinity of the polymer. Combined with chemical properties of DPP-polymers and putrescine molecules, it was proposed that the trapping effect of lone pairs of electrons on putrescine molecules would cause the responses of DPP-OTFT sensors. Mobility dropping, drain-source current decrease and negative shift of VTH were observed with DPP-sensors by this trapping effect with the diffused PUT in the active channel. Future steps are expected based on this study. Better sensing ability can be achieved with the improvement on both transistors quality and polymers properties. More accurate relationships between sensors responses and PUT vapor concentrations can be built by optimizing gas sensing process. Spoilage detection of food products with OTFT sensors can be improved for more precise analysis with assistance of liquid chromatography (LC) and gas chromatography (GC). The ultimate goal of this study is to manufacture smart labels or tags with OTFT-sensors to attach on food packages, by connecting to smartphones or computers, fulfilling a real-time, in-situ detection of PUT vapor with ideal accuracy.
Download or read book Fundamentals and Applications of Chemical Sensors written by Dennis Schuetzle and published by . This book was released on 1986 with total page 416 pages. Available in PDF, EPUB and Kindle. Book excerpt: Presents the first comprehensive collection of articles on the fundamentals and applications of a wide variety of chemical sensors. Discusses a range of topics from the development of new sensor concepts to improvement in sensors that have been mass produced for several years. Specific types of sensors discussed include oxygen, electrochemical, microbial, drug, and glucose sensors.
Download or read book In situ Real time Spectroscopy Platform for Monitoring Gas Adsorption and Reactions on 2D Materials written by Milo Holt and published by . This book was released on 2019 with total page 204 pages. Available in PDF, EPUB and Kindle. Book excerpt: Thin film gas sensors are at the center of critical areas of research and innovation, with applications in a wide range of important and fast-evolving fields. From environmental monitoring and medical diagnosis to early warning systems and safety, gas sensors are a vital front end technology already ubiquitous in industry. With development of the Internet of Things (IoT), the need for untethered platforms is accelerating the search for gas sensing materials suitable in low-power applications. 2D materials like graphene and 40+ combinations of the transition metal dichalcogenides (TMDs) show particular promise here, owing to a suite of exceptional dimensional, structural and electronic properties. Specifically with respect to gas sensing, 2D thin films provide the ultimate material dimensions and properties for low-power fast-response devices, at the same time providing an excellent interface for analyte-surface observations. This dissertation concerns the sensing properties and stability of the four prototypical semiconducting TMD combinations of molybdenum (Mo), Tungsten (W), Sulfur (S) and Selenium (Se), with a focus on molybdenum disulfide (MoS2). This work presents a platform solution for the in-situ real-time (dynamic) capture and study of ammonia (NH3), water vapor (H2O) and oxygen (O2) interactions with exfoliated and synthesiszed TMDs in a controlled environment, at both ambient and elevated temperatures
Download or read book Metallo organic Deposition of Tin Oxide Thin Films for Gas Sensing Devices written by Shin-Chia Chang and published by . This book was released on 1985 with total page 14 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Metal Organic Framework Materials written by Leonard R. MacGillivray and published by John Wiley & Sons. This book was released on 2014-09-19 with total page 1210 pages. Available in PDF, EPUB and Kindle. Book excerpt: Metal-Organic Frameworks (MOFs) are crystalline compounds consisting of rigid organic molecules held together and organized by metal ions or clusters. Special interests in these materials arise from the fact that many are highly porous and can be used for storage of small molecules, for example H2 or CO2. Consequently, the materials are ideal candidates for a wide range of applications including gas storage, separation technologies and catalysis. Potential applications include the storage of hydrogen for fuel-cell cars, and the removal and storage of carbon dioxide in sustainable technical processes. MOFs offer the inorganic chemist and materials scientist a wide range of new synthetic possibilities and open the doors to new and exciting basic research. Metal-Organic Frameworks Materials provides a solid basis for the understanding of MOFs and insights into new inorganic materials structures and properties. The volume also reflects progress that has been made in recent years, presenting a wide range of new applications including state-of-the art developments in the promising technology for alternative fuels. The comprehensive volume investigates structures, symmetry, supramolecular chemistry, surface engineering, recognition, properties, and reactions. The content from this book will be added online to the Encyclopedia of Inorganic and Bioinorganic Chemistry: http://www.wileyonlinelibrary.com/ref/eibc
Download or read book Some Studies on Gas sensing Organic Semiconductors written by and published by . This book was released on 1983 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Scientific and Technical Aerospace Reports written by and published by . This book was released on 1995 with total page 692 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Nanocomposites written by and published by BoD – Books on Demand. This book was released on 2024-09-25 with total page 368 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book discusses the development, characterization, and applications of nanocomposites, which are advanced materials obtained through the combination of two or more constituents, with one being a continuous phase (matrix) and the other being a discontinuous or dispersed nanophase. Nanocomposites have gained significant attention due to their excellent properties and multiple applications, resulting from synergistic effects between the matrix and reinforced nanophase. Nanocomposites offer advantages over individual nanoparticles in tailoring properties, enhancing stability, and optimizing performance for specific applications. This book emphasizes the vast potential of nanocomposites in various areas, including water treatment, food packaging, automotive compounds, biomedical devices, coatings, sensors, pharmaceuticals, and fuel cells, among others. The properties of nanocomposites are highly dependent on their structure and dimensions, and further research is needed to better understand the structure-property relationship in these systems. The book includes sixteen chapters organized into four sections: “Carbon-Based Nanocomposites”, “Inorganic Nanoparticles-Based Nanocomposites”, “Nanocomposites for Environmental Applications”, and “Nanocomposites for Biomedical Applications”.
Download or read book Study of Organic Optical Thin Films for Bio chemical Sensing written by Courtney Lavasia Boykin and published by . This book was released on 2010 with total page 140 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Acid Precipitation written by and published by . This book was released on 1994 with total page 1044 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Gas Sensors Using Organic Thin Films at Room Temperature written by N. E. Agbor and published by . This book was released on 1993 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Morphological and Electrical Studies of Organic Semiconductor Thin Films written by Serkan Zorba and published by . This book was released on 2004 with total page 250 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book SEIA 2019 Conference Proceedings written by Sergey Yurish and published by Lulu.com. This book was released on 2020-01-13 with total page 349 pages. Available in PDF, EPUB and Kindle. Book excerpt: Proceedings of the 5th International Conference on Sensors and Electronic Instrumentation Advances SEIA' 2019), 25-27 September 2019, Tenerife (Canary Islands), Spain. The coverage includes: various physical sensors, gas sensors, optical and fiber optical sensors and systems, biosensors, sensors networks and applications.
Download or read book On Solar Hydrogen and Nanotechnology written by Lionel Vayssieres and published by John Wiley & Sons. This book was released on 2010-01-26 with total page 706 pages. Available in PDF, EPUB and Kindle. Book excerpt: More energy from the sun strikes Earth in an hour than is consumed by humans in an entire year. Efficiently harnessing solar power for sustainable generation of hydrogen requires low-cost, purpose-built, functional materials combined with inexpensive large-scale manufacturing methods. These issues are comprehensively addressed in On Solar Hydrogen & Nanotechnology – an authoritative, interdisciplinary source of fundamental and applied knowledge in all areas related to solar hydrogen. Written by leading experts, the book emphasizes state-of-the-art materials and characterization techniques as well as the impact of nanotechnology on this cutting edge field. Addresses the current status and prospects of solar hydrogen, including major achievements, performance benchmarks, technological limitations, and crucial remaining challenges Covers the latest advances in fundamental understanding and development in photocatalytic reactions, semiconductor nanostructures and heterostructures, quantum confinement effects, device fabrication, modeling, simulation, and characterization techniques as they pertain to solar generation of hydrogen Assesses and establishes the present and future role of solar hydrogen in the hydrogen economy Contains numerous graphics to illustrate concepts, techniques, and research results On Solar Hydrogen & Nanotechnology is an essential reference for materials scientists, physical and inorganic chemists, electrochemists, physicists, and engineers carrying out research on solar energy, photocatalysis, or semiconducting nanomaterials, both in academia and industry. It is also an invaluable resource for graduate students and postdoctoral researchers as well as business professionals and consultants with an interest in renewable energy.
