Download or read book Nitrogen doped Titanium Dioxide Thin Films written by Justin M. Hamblin and published by . This book was released on 2009 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Visible Light Absorption by Nitrogen doped Titanium Dioxide Thin Films with 011 Facets for Photocatalysis written by Mana Moarrefzadeh and published by . This book was released on 2016 with total page 130 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Nitrogen and Carbon doped Titanium Dioxide Thin Films for Solar Hydrogen Generation written by Meghan E. Schulz and published by . This book was released on 2009 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Photoelectrochemical cells (PECs) are integrated devices that split water using only clean power from the sun, thus producing clean hydrogen fuel with no harmful carbon emissions. The search is on for optimal photoanode materials in PECs. Desired properties include adequate supply, non-toxicity, stability in aqueous solution, ability to split water, and ability to absorb most of the solar spectrum. Titanium dioxide satisfies all but this last criterion; with a bandgap near 3 eV, only the ultraviolet (UV) range of the spectrum may be used. This thesis reports on attempts to improve the visible light activity of TiO 2 by doping with the nonmetals nitrogen and carbon, in order to lower effective bandgap. We have synthesized sets of N- and C-containing TiO 2 via a simple, easily controlled physical vapor deposition (PVD) process known as pulsed laser deposition (PLD). The dopants were introduced by means of a carrier gas: either nitrogen or methane. Atomic concentrations of dopant were found via X-ray photoelectron spectroscopy (XPS) to range from 0-4%. Pure TiO 2 deposits in polycrystalline anatase form at 600°C; nitrogen-doped films were also anatase, while carbon incorporation caused a shift to mixed anatase/rutile character. XPS scans showed changes in electronic structure with increased dopant concentration. In the case of nitrogen, a distinct Ti-N peak appeared, indicating N atoms substituting for O. Carbon-region scans only showed a Ti-C peak at high carbon concentrations. Valence band scans of both C-TiO 2 and N-TiO 2 showed distinct doping states developing just above the valence band. Nitrogen proved more adept at improving visible light activity; with a quantum efficiency peak near 460 nm, and a UV-Visible absorption edge at 510 nm. No such visible light activity resulted from carbon-doping. It is theorized that the carbon states are too deep within the bandgap to significantly increase visible light activity, unlike nitrogen 1s states, which successfully overlap with valence band O2p states.
Download or read book Photocatalytic Activity of Nitrogen Doped TiO2 Filtered vacuum arc Deposited Thin Films written by Ines Chayun and published by . This book was released on 2011 with total page 102 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Photocatalytic Activity Enhancement of Titanium Dioxide Nanoparticles written by Mohamed A. Barakat and published by Springer. This book was released on 2015-10-26 with total page 39 pages. Available in PDF, EPUB and Kindle. Book excerpt: In this brief, a comprehensive review of the UV/visible-TiO2 photocatalytic oxidation process is presented with an insight into the mechanisms involved, the role of titanium dioxide as a catalyst, irradiation sources, types of reactors, and a comparison between various modes of TiO2 application. An overview of the development and enhancement of the activity of TiO2 nanoparticles in photocatalysis is presented. The topics covered include a detailed look at the unique properties of the TiO2 nanoparticles and their relationship to photocatalytic properties. The utilization of the TiO2 nanoparticles as photocatalysts, in the non-doped and doped forms is also reviewed. Finally, the use of modified TiO2 nanoparticles has made a significant contribution in providing definitive mechanistic information regarding the visible light photocatalytic processes.
Download or read book ToF SIMS written by J. C. Vickerman and published by IM Publications. This book was released on 2013 with total page 742 pages. Available in PDF, EPUB and Kindle. Book excerpt: Time-of-flight secondary ion mass spectrometry (ToF-SIMS) is the most versatile of the surface analysis techniques that have been developed during the last 30 years. This is the Second Edition of the first book ToF-SIMS: Surface analysis by Mass Spectrometry to be dedicated to the subject and the treatment is comprehensive
Download or read book Chemically Deposited Nanocrystalline Metal Oxide Thin Films written by Fabian I. Ezema and published by Springer Nature. This book was released on 2021-06-26 with total page 926 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book guides beginners in the areas of thin film preparation, characterization, and device making, while providing insight into these areas for experts. As chemically deposited metal oxides are currently gaining attention in development of devices such as solar cells, supercapacitors, batteries, sensors, etc., the book illustrates how the chemical deposition route is emerging as a relatively inexpensive, simple, and convenient solution for large area deposition. The advancement in the nanostructured materials for the development of devices is fully discussed.
Download or read book Homogeneous and Heterogeneous Photocatalysis written by E. PELIZZETTI and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 720 pages. Available in PDF, EPUB and Kindle. Book excerpt: Ever since the oil crisis of 1973, researchers in various fields of chemistry have proposed various schemes to conserve energy, as well to convert the sun's abundant and limitless supply of energy to produce chemical fuels (e. g. , hydrogen from water, . •. ). The enthusiasm had no previous parallel in the mid-1970's. Unfortunately, despite the several good proposals, the results have proven - in retrospect - somewhat disappointing from an economic viable point of view. The reasons for the meagre results are manyfold not the least of which are the experimental difficulties encountered in storage systems. Moreover, the lack of a concerted, well orchestrated interdisciplinary approach has been significant. By contrast, the chemical advances made in the understanding of the processes involved in such schemes have been phenomenal. A recent book on this issue ( M. Gratzel, Energy Resources through Photochemistry and Catalysis, 1983) is witness to the various efforts and approaches taken by researchers. In the recent years, many more groups have joined in these efforts, and the number of papers in the lit~rature is staggering ! One of the motives for organizing this NATO Advanced Research Workshop stemmed from our view that it was time to take stock of the accomplishments and rather than propose new schemes, it was time to consider seriously avenues that are most promising.
Download or read book Titanium Dioxide written by Dongfang Yang and published by BoD – Books on Demand. This book was released on 2018-06-27 with total page 520 pages. Available in PDF, EPUB and Kindle. Book excerpt: Titanium dioxide is currently being used in many industrial products. It provides unique photocatalytic properties for water splitting and purification, bacterial inactivation, and organics degradation. It has also been widely used as the photoanode for dye-sensitized solar cells and coatings for self-cleaning surfaces, biomedical implants, and nanomedicine. This book covers various aspects of titanium dioxide nanomaterials including their unique one-dimensional, two-dimensional, mesoporous, and hierarchical nanostructures and their synthetic methods such as sol-gel, hydrothermal, anodic oxidation, and electrophoretic deposition, as well as its key applications in environmental and energy sectors. Through these 24 chapters written by experts from the international scientific community, readers will have access to a comprehensive overview of the recent research and development findings on the titanium dioxide nanomaterials.
Download or read book Improving the Optoelectronic Property and Photoactivity of Nano structured Titanuim Dioxide written by Hong-Ying Lin and published by ProQuest. This book was released on 2008 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Titanium dioxide (TiO 2) has been proven to be one of the most important and widely used photocatalyst for applications such as gas/liquid phase environmental cleaning, solar hydrogen generation, sensitized solar cell, UV filtration, etc. The biggest challenge in the applications of this semiconductor photocatalyst is its large band gap (~ 3.2 eV) which limits the utilizable spectrum of photons from the solar light (~ 4 to 5 %). To improve the optical sensitivity of TiO 2 in the visible light region, the band gap of TiO 2 needs to be tailored. The reduction of TiO 2 band gap can be achieved by controlling of its electronic structure via two routes: changing the particle size and doping it with impurities. To precisely control the size of TiO 2 particles, anatase TiO 2 nanocrystallines (17 to 29 nm) were synthesized by metallo-organic chemical vapor deposition (MOCVD) method with moderate control on system parameters (i.e. pressure and gas flow rates). The results of band gap change as a function of particle size agreed well with what was predicted using the Brus' effective mass model (EMM). However, the observations from photocatalytic oxidation of 2-chlorophenol (2-CP) showed that the smaller the particle size, the faster the degradation rate. This is attributed in part to the combined effect of band gap change relative to the spectrum of the light source and the specific surface area (or particle size) of the photocatalysts. Our results indicate that the gain in specific surface area due to the smaller particle size outweighs the improvement on its optical property (e.g. reduction in bandgap) under similar experimental condition. Our observation also showed the secondary particle size to be time dependent due to the aggregation and is highly correlated with its primary particle size. The nitrogen doped TiO 2 thin film synthesis was carried out with two different approaches: (1) oxidation of the titanium nitride (TiN) thin film and (2) reactive pulsed laser deposition (PLD). Nitrogen doping of TiO 2 in the former approach was done by the oxidation of TiN thin films at 800 ̊C in ambient air. The phase transformation of TiN to TiO 2 appears to be a function of annealing time. The X-ray photoelectron spectroscopy (XPS) studies have shown that the substitutionally doped TiO 2-x N x (N 1 s ~ 396 eV) remains stable only for the first two minutes of annealing. As the annealing proceeds, the N 1s XPS peak shifts to higher binding energy (N1 s ~ 400 and 402 eV) which indicates that binding energy of N atom shifted from substitutional site (Ti-N) to chemisorbed site (N=-N) when annealing process exceeds five minutes due to the substitution of Ti-N bond by Ti-O bond. Results from both depth profile XPS and cross-section TEM showed that the formation of TiO 2-x N x depends on the distance from the film surface. Film structure studied by X-ray diffraction (XRD) showed that mixed TiN and rutile TiO 2 phases formed between four and twenty four hours of annealing time. The optical properties were examined using UV-VIS spectroscopy. The most visible light sensitive samples showed ~65 to 105 nm red-shift on its absorption edges from that of pure TiO 2, which is equivalent to ~0.47 to 0.73 eV reduction in the effective bandgap. Our results suggest that surface oxidation of TiN is an effective method for the synthesis of band gap tailored oxides which have applications in photocatalysis, photovoltaic, etc. Doping of N into TiO 2 lattice was also achieved using the reactive pulsed laser deposition technique. The N concentration was controlled by adjusting the mixing ratio of make-up (N 2) and buffer (1:1 O 2 and Ar mixture) gases during laser ablation. (Abstract shortened by UMI.).
Download or read book Advanced Strategies in Thin Film Engineering by Magnetron Sputtering written by Alberto Palmero and published by MDPI. This book was released on 2020-12-10 with total page 148 pages. Available in PDF, EPUB and Kindle. Book excerpt: Recent years have witnessed the flourishing of numerous novel strategies based on the magnetron sputtering technique aimed at the advanced engineering of thin films, such as HiPIMS, combined vacuum processes, the implementation of complex precursor gases or the inclusion of particle guns in the reactor, among others. At the forefront of these approaches, investigations focused on nanostructured coatings appear today as one of the priorities in many scientific and technological communities: The science behind them appears in most of the cases as a "terra incognita", fascinating both the fundamentalist, who imagines new concepts, and the experimenter, who is able to create and study new films with as of yet unprecedented performances. These scientific and technological challenges, along with the existence of numerous scientific issues that have yet to be clarified in classical magnetron sputtering depositions (e.g., process control and stability, nanostructuration mechanisms, connection between film morphology and properties or upscaling procedures from the laboratory to industrial scales) have motivated us to edit a specialized volume containing the state-of-the art that put together these innovative fundamental and applied research topics. These include, but are not limited to: • Nanostructure-related properties; • Atomistic processes during film growth; • Process control, process stability, and in situ diagnostics; • Fundamentals and applications of HiPIMS; • Thin film nanostructuration phenomena; • Tribological, anticorrosion, and mechanical properties; • Combined procedures based on the magnetron sputtering technique; • Industrial applications; • Devices.
Download or read book Semiconductor Photocatalysis written by Wenbin Cao and published by BoD – Books on Demand. This book was released on 2016-08-24 with total page 678 pages. Available in PDF, EPUB and Kindle. Book excerpt: Photocatalysis is a hot topic because it is an environmentally friendly approach toward the conversion of light energy into chemical energy at mild reaction environments. Also, it is well applied in several major areas such as water splitting, bacterial inactivation, and pollutants elimination, which is a possible solution to energy shortage and environmental issues. The fundamental knowledge and the frontier research progress in typical photocatalytic materials, such as TiO2-based and non-TiO2-based photocatalysts, are included in this book. Methods to improve the photocatalytic efficiency and to provide a hint for the rational design of the new photocatalysts are covered.
Download or read book Environmentally Benign Photocatalysts written by Masakazu Anpo and published by Springer Science & Business Media. This book was released on 2010-11-11 with total page 740 pages. Available in PDF, EPUB and Kindle. Book excerpt: Over the past few decades, mankind has observed an unprecedented and remarkable growth in industry, resulting in a more prosperous lifestyle for peoples of many countries. In developing countries, however, explosive industrial growth is just now beginning to raise the living standards of the people. Most industries, especially in these developing countries, are still powered by the burning of fossil fuels; con- quently, a lack of clean energy resources has caused environmental pollution on an unprecedented large and global scale. Toxic wastes have been relentlessly released into the air and water leading to serious and devastating environmental and health problems while endangering the planet and life itself with the effects of global warming. To address these urgent environmental issues, new catalytic and photocatalytic processes as well as open-atmospheric systems are presently being developed that can operate at room temperature while being totally clean and ef?cient and thus environmentally harmonious. Essential to technologies harnessing the abundant solar energy that reaches the earth are the highly functional photocatalytic proce- es that can utilize not only UV light, but also visible light.
Download or read book Titanium Dioxide TiO2 and Its Applications written by Francesco Parrino and published by Elsevier. This book was released on 2020-11-29 with total page 735 pages. Available in PDF, EPUB and Kindle. Book excerpt: Scientific interest in TiO2-based materials has exponentially grown in the last few decades. Titanium Dioxide (TiO2) and Its Applications introduces the main physicochemical properties of TiO2 which are the basis of its applications in various fields. While the basic principles of the TiO2 properties have been the subject of various previous publications, this book is mainly devoted to TiO2 applications. The book includes contributions written by experts from a wide range of disciplines in order to address titanium dioxide's utilization in energy, consumer, materials, devices, and catalytic applications. The various applications identified include: photocatalysis, catalysis, optics, electronics, energy storage and production, ceramics, pigments, cosmetics, sensors, and heat transfer. Titanium Dioxide (TiO2) and Its Applications is suitable for a wide readership in the disciplines of materials science, chemistry, and engineering in both academia and industry. Includes a wide range of current and emerging applications of titanium dioxide in the fields of energy, consumer applications, materials, and devices Provides a brief overview of titanium dioxide and its properties, as well as techniques to design, deposit, and study the material Discusses the relevant properties, preparation methods, and other apposite considerations in each application-focused chapter
Download or read book Photochemistry written by Angelo Albini and published by Royal Society of Chemistry. This book was released on 2013 with total page 371 pages. Available in PDF, EPUB and Kindle. Book excerpt: Annotation 'Photochemistry' reviews photo-induced processes that have relevance to the wide-ranging academic and commercial disciplines, and interests in chemistry, physics, biology and technology.
Download or read book Thin Film Structures in Energy Applications written by Suresh Babu Krishna Moorthy and published by Springer. This book was released on 2015-03-10 with total page 300 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book provides a comprehensive overview of thin film structures in energy applications. Each chapter contains both fundamentals principles for each thin film structure as well as the relevant energy application technologies. The authors cover thin films for a variety of energy sectors including inorganic and organic solar cells, DSSCs, solid oxide fuel cells, thermoelectrics, phosphors and cutting tools.
Download or read book Industrial Applications of Nanoparticles written by Marta Irene Litter and published by CRC Press. This book was released on 2023-03-31 with total page 491 pages. Available in PDF, EPUB and Kindle. Book excerpt: Nanotechnology is one of the most rapidly developing areas of science, with great potential to solve the developmental challenges in a wide range of industries such as aerospace, agriculture, bioengineering, cosmetics, chemicals, electronics, energy, renewables, surface coatings, textiles, medicine, materials manufacturing, military equipment, etc. To compile this book, distinguished scientists, engineers, and industrial professionals from different parts of the world have been invited. An array of 17 high-quality science-based chapters covering recent advancements, challenges, and future trends in industrial applications of nanotechnology is presented. The book is aimed at industrial professionals and graduate-level students and researchers.
