Download or read book Fabrication and Characterization Studies of Co doped Zinc Oxides written by 陳柏烜 and published by . This book was released on 2014 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Fabrication and Characterization of Si Doped ZnO and Cu2P2O7 Thin Films written by Jiale Wang and published by . This book was released on 2019 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Fabrication and Characterization of Zinc Oxide Zno Nanostructures written by Yu-Hang Leung and published by . This book was released on 2017-01-27 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Fabrication and Characterization of Metal Oxide Nanostructures written by Dan Li and published by Open Dissertation Press. This book was released on 2017-01-27 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: This dissertation, "Fabrication and Characterization of Metal Oxide Nanostructures" by Dan, Li, 李丹, was obtained from The University of Hong Kong (Pokfulam, Hong Kong) and is being sold pursuant to Creative Commons: Attribution 3.0 Hong Kong License. The content of this dissertation has not been altered in any way. We have altered the formatting in order to facilitate the ease of printing and reading of the dissertation. All rights not granted by the above license are retained by the author. Abstract: Abstract of thesis entitled FABRICATION AND CHARACTERIZATION OF METAL OXIDE NANOSTRUCTURES Submitted by Li Dan for the degree of Doctor of Philosophy at The University of Hong Kong in July 2007 Among various nanostructured materials, metal oxides are very promising for a variety of practical applications. Among different possible synthesis methods for metal oxide nanostructures, hydrothermal synthesis is of great interest because it is safe and environmentally friendly, and is typically performed at temperatures of less than 200 C. In this dissertation, several metal oxide nanostructures, including zinc oxide (ZnO), copper oxide (CuO) and nickel oxide (NiO) nanostructures, were fabricated by hydrothermal synthesis from aqueous solutions of zinc/copper/nickel nitrate hydrate and hexamethylenetetramine. The morphological, structural, optical and electrochemical properties of resultant nanostructures were studied by scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffractometry (XRD), energy dispersive X-ray spectroscopy (EDX), photoluminescence (PL), and electron paramagnetic resonance spectroscopy (EPR). The obtained ZnO nanorods are straight and perpendicular to the substrate. The substrate conditions have considerable effects on the size and the orientation of the nanorods. The pH value of solutions also has significant influence on the morphology of resultant ZnO nanostructures. The PL spectra of the ZnO nanorods exhibit one UV peak and one yellow peak ( 578 nm). The ZnO nanorods also show very strong EPR signal at g 1.96. For different synthesis conditions, spherical assemblies of CuO platelets and CuO nanostructured films were obtained respectively. The solution concentration, pH value, synthesis temperature, and presence of seeds significantly affect obtained morphology as well as adhesion to the substrate. For different synthesis conditions, NiO nanowalls and NiO nanostructured films were obtained respectively. The influence of pH value is different on different NiO nanostructures. Finally, transition metal (Mn, Cr, and Co) doped ZnO nanostructures were synthesized by a hydrothermal method from aqueous solutions of zinc nitrate hydrate, TM (TM = Mn, Cr, Co) nitrate hydrate, and hexamethylenetetramine. The addition of TM nitrate hydrate resulted in the change of the shape and preferential orientation of ZnO nanorods. Also, the addition of the dopant affects the optical properties, including the ratio of UV to defect emission and the position of the UV emission peak. DOI: 10.5353/th_b3877735 Subjects: Nanostructures Metallic oxides

Download or read book Zinc Oxide Nanostructures Synthesis and Characterization written by Sotirios Baskoutas and published by MDPI. This book was released on 2018-12-04 with total page 303 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book is a printed edition of the Special Issue "Zinc Oxide Nanostructures: Synthesis and Characterization" that was published in Materials

Download or read book Oxide Thin Films Multilayers and Nanocomposites written by Paolo Mele and published by Springer. This book was released on 2015-03-26 with total page 320 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book provides a comprehensive overview of the science of nanostructured oxides. It details the fundamental techniques and methodologies involved in oxides thin film and bulk growth, characterization and device processing, as well as heterostructures. Both, experts in oxide nanostructures and experts in thin film heteroepitaxy, contribute the interactions described within this book.

Download or read book Zinc Oxide and Manganese Doped Zinc Oxide Nanoparticles written by Yadollah Abdollahi and published by LAP Lambert Academic Publishing. This book was released on 2012-06 with total page 192 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book consists of synthesis and characterization of ZnO and Mn-doped ZnO nanoparticles for photocatalyst process. The work contains synthesis (co- precipitation), Characterization (TEM, SEM, EDX, FTIR, XRD, BET, UV-visible NIR) and application of ZnO and Mn-doped ZnO nanoparticles. The application included photodegradation of m-, o- and p-cresol that was carried out under UV and visible irradiation at room temperature, atmospheric pressure, and different PH by batch photoreactors. The intermediates were identified by UPLC and mineralization was confirmed by TOC measurement. As a result, 1%wt Mn-doped ZnO with lower particles size, higher surface area, high cresols adsorption, lower agglomerate, appropriate band gap and higher photodegradation ability than other % of Mn-doped ZnO is the best photocatalyst that may enhance the photocatalyst activity of ZnO under visible light. "

Download or read book Processing and Characterization of P Type Doped Zinc Oxide Thin Films written by Michelle Anne Myers and published by . This book was released on 2013 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Applications of zinc oxide (ZnO) for optoelectronic devices, including light emitting diodes, semiconductor lasers, and solar cells have not yet been realized due to the lack of high-quality p-type ZnO. In the research presented herein, pulsed laser deposition is employed to grow Ag-doped ZnO thin films, which are characterized in an attempt to understand the ability of Ag to act as a p-type dopant. By correlating the effects of the substrate temperature, oxygen pressure, and laser energy on the electrical and microstructural properties of Ag-doped ZnO films grown on c-cut sapphire substrates, p-type conductivity is achieved under elevated substrate temperatures. Characteristic stacking fault features have been continuously observed by transmission electron microscopy in all of the p-type films. Photoluminescence studies on n-type and p-type Ag-doped ZnO thin films demonstrate the role of stacking faults in determining the conductivity of the films. Exciton emission attributed to basal plane stacking faults suggests that the acceptor impurities are localized nearby the stacking faults in the n-type films. The photoluminescence investigation provides a correlation between microstructural characteristics and electrical properties of Ag- doped ZnO thin films; a link that enables further understanding of the doping nature of Ag impurities in ZnO. Under optimized deposition conditions, various substrates are investigated as potential candidates for ZnO thin film growth, including r -cut sapphire, quartz, and amorphous glass. Electrical results indicated that despite narrow conditions for obtaining p-type conductivity at a given substrate temperature, flexibility in substrate choice enables improved electrical properties. In parallel, N+-ion implantation at elevated temperatures is explored as an alternative approach to achieve p-type ZnO. The ion implantation fluence and temperature have been optimized to achieve p-type conductivity. Transmission electron microscopy reveals that characteristic stacking fault features are present throughout the p-type films, however in n-type N-doped films high-density defect clusters are observed. These results suggest that the temperature under which ion implantation is performed plays a critical role in determining the amount of dynamic defect re- combination that can take place, as well as defect cluster formation processes. Ion implantation at elevated temperatures is shown to be an effective method to introduce increased concentrations of p-type N dopants while reducing the amount of stable post-implantation disorder. Finally, the fabrication and properties of p-type Ag-doped ZnO/n-type ZnO and p-type N-doped ZnO/n-type ZnO thin film junctions were reported. For the N-doped sample, a rectifying behavior was observed in the I-V curve, consistent with N-doped ZnO being p-type and forming a p-n junction. The turn-on voltage of the device was -2.3 V under forward bias. The Ag-doped samples did not result in rectifying behavior as a result of conversion of the p-type layer to n-type behavior under the n- type layer deposition conditions. The systematic studies in this dissertation provide possible routes to grow p-type Ag-doped ZnO films and in-situ thermal activation of N-implanted dopant ions, to overcome the growth temperature limits, and to push one step closer to the future integration of ZnO-based devices. The electronic version of this dissertation is accessible from http://hdl.handle.net/1969.1/149354

Download or read book Nanostructured Materials written by Mohindar Seehra and published by BoD – Books on Demand. This book was released on 2017-07-12 with total page 225 pages. Available in PDF, EPUB and Kindle. Book excerpt: There continues to be a worldwide interest in the size-dependent properties of nanostructured materials and their applications in many diverse fields such as catalysis, sensors, energy conversion processes, and biomedicine to name a few. The eleven chapters of this book written by different researchers include four chapters on the different methods of fabrication of specific materials followed by characterization of their properties, and the remaining seven chapters focusing on the fabrications and applications including three chapters on biomedical applications, two chapters on sensors, one chapter on solar cells, and one chapter on the use of nanoparticles in herbicides. These chapters provide up-to-date reviews useful for current and future researchers in these specific areas.

Download or read book Fabrication and characterization of zno nanostructures and highly doped er3 zno films written by Tracy M. Williams and published by . This book was released on 2006 with total page 57 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Fabrication and Characterization of Cobalt Pigmented Anodized Zinc for Photocatalytic Application written by Judith Chebwogen and published by . This book was released on 2019 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Population growth and urbanization have led to water scarcity and pollution, which is a health hazard not only to humans but also to the ecosystem in general. This has necessitated coming up with ways of treating water before consumption. Photocatalysis has proved to be one of the most promising cheap techniques that involve chemical utilization of solar energy. TiO2 widely used in photocatalysis absorbs a narrow range of the solar spectrum compared to ZnO. In this regard, this study aimed at preparing and optimizing cobalt-pigmented ZnO, which is applicable in photocatalytic water treatment. The objectives in this study were to fabricate zinc oxide (ZnO) thin films by anodization, pigment the fabricated films with varying cobalt concentrations, characterize the fabricated films optically, and investigate the cobalt-pigmented ZnO,Äôs performance in the methylene blue degradation under UV light irradiation. Mirror-polished zinc plates were sonicated in ethanol and rinsed. Anodization was done at room temperature in 0.5¬†M oxalic acid at a constant voltage of 10¬†V for 60¬†min, and cobalt electrodeposited in the films. Post-deposition treatment was done at 250¬∞C. Optical properties of the films were studied using a UV-VIS- NIR spectrophotometer in the solar range of 300,Äì2500¬†nm. The photocatalytic activity of the fabricated films was studied in methylene blue solution degradation in the presence of UV light irradiation for 5¬†h. Cobalt pigmenting was observed to reduce reflectance and optical band gap from 3.34 to 3.10¬†eV indicating good photocatalytic properties. In this study, ZnO film pigmented with cobalt for 20 s was found to be the most photocatalytic with a rate constant of 0.0317¬†h,àí1 and hence had the optimum cobalt concentration for photocatalytic water treatment. This can be applied in small-scale water purification.

Download or read book Fabrication and Characterization of ZnO Based Photodetectors and Light emitting Diodes written by Leelaprasanna Mandalapu Jayaramulu and published by . This book was released on 2008 with total page 314 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Fabrication and Characterization of Zinc Oxide Nanostructures for Piezoelectric Mechanical and Electrical Applications written by and published by . This book was released on 2014 with total page 138 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Optical Characterization of Doped Zinc Oxide Nanowires written by Faezeh Mohammadbeigi and published by . This book was released on 2017 with total page 126 pages. Available in PDF, EPUB and Kindle. Book excerpt: ZnO is a promising semiconductor material with a direct band gap energy of 3.3 eV which makes it a good candidate for UV and visible range light emitting devices. Metalorganic chemical vapour epitaxy (MOVPE) provides the possibility of industrial scale growth of ZnO, with very fine control of impurity dopants. Despite the vast recent literature on ZnO, there are very few studies of systematic intentional doping. ZnO nanowires (NWs) can be grown easily on various substrates with high crystalline quality and low defect densities and tend to exhibit reduced substrate induced strain. This enables us to perform careful spectroscopic analysis of impurity related optical transitions and identify the physical nature of various dopant species. A detailed study of low temperature photoluminescence (PL) transitions in doped ZnO NWs, thin films, and bulk crystals grown by MOVPE and chemical vapour transport (CVT) methods is presented. The standard group III donors were first investigated. Donor bound exciton (D0X) transitions previously assigned to Ga, Al, and In were confirmed in intentionally doped samples. Group IV dopants such as carbon, and tin are interesting since they can act in principle as double donors or double acceptors. We report four new shallow D0X transitions (Z-lines), at 3360.8 (Z1), 3361.2 (Z2), 3361.7 (Z3) and 3361.9 (Z4) meV, which can be greatly enhanced by co-doping with carbon tetrachloride and hydrogen. These shallow donors appear to be due to carbon impurities complexed with other unknown defects in four distinct configurations. Carbon-doped samples also exhibit two distinct acceptors with binding energies of 133 ± 5 and 181 ± 5 meV. Doping concentration and temperature dependent PL studies of unintentionally doped and Sn-doped ZnO single crystals confirmed emission from the I10 D0X transition which was recently proven to contain Sn on a Zn site. Sb-doped ZnO NWs were grown in an attempt to produce p-type material as reported by some groups. Our PL studies including Magneto PL, have shown that rather than p-doped material, the addition of small amounts of Sb-dopant resulted in a new PL transition at 3364.3 meV, which turns out to be the shallowest D0X transition so far observed in ZnO.

Download or read book Fabrication and Characterization of Zinc Oxide ZnO Nanostructures written by Yu-hang Leung and published by . This book was released on 2006 with total page 190 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Ceramic Science and Engineering written by Kamakhya Prakash Misra and published by Elsevier. This book was released on 2022-05-03 with total page 618 pages. Available in PDF, EPUB and Kindle. Book excerpt: Ceramic Science and Engineering: Basics to Recent Advancements covers the fundamentals, classification and applications surrounding ceramic engineering. In addition, the book contains an extensive review of the current published literature on established ceramic materials. Other sections present an extensive review of up-to-date research on new innovative ceramic materials and reviews recently published articles, case studies and the latest research outputs. The book will be an essential reference resource for materials scientists, physicists, chemists and engineers, postgraduate students, early career researchers, and industrial researchers working in R&D in the development of ceramic materials. Ceramic engineering deals with the science and technology of creating objects from inorganic and non-metallic materials. It combines the principles of chemistry, physics and engineering. Fiber-optic devices, microprocessors and solar panels are just a few examples of ceramic engineering being applied in everyday life. Advanced ceramics such as alumina, aluminum nitride, zirconia, ZnO, silicon carbide, silicon nitride and titania-based materials, each of which have their own specific characteristics and offer an economic and high-performance alternative to more conventional materials such as glass, metals and plastics are also discussed. - Covers environmental barrier ceramic coatings, advanced ceramic conductive fuel cells, processing and machining technology in ceramic and composite materials, photoluminescent ceramic materials, perovskite ceramics and bioinspired ceramic materials - Reviews both conventional, established ceramics and new, innovative advanced ceramics - Contains an extensive review of the current published literature on established ceramic materials

Download or read book Fabrication and Characterization of Zinc Oxide ZnO Nanowires Array and Its Applications written by Yu Hang Leung and published by . This book was released on 2011 with total page 214 pages. Available in PDF, EPUB and Kindle. Book excerpt: