Download or read book Photoelectrochemical Activity of Titanium Dioxide Thin Films written by Aida Mehdinezhad Roshan and published by . This book was released on 2013 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Titanium dioxide (TiO2) is considered as an oxide semiconductor with several unique properties, including environmental sensing capabilities, biocompatibility and photocurrent generation, long-term stability, cost efficiency, and chemical inertness. TiO2 thin films have a wide range of applications in dye-sensitized solar cells. TiO2 films have been deposited on two different substrates, aluminum and titanium. Two different methods used for deposition of the thin films namely: Plasma Electrolytic Oxidation (PEO) and Physical Vapor Deposition (PVD). In order to study the effect of roughness of the substrate on photocurrent generation of the deposited films, one group of substrates were "patterned" by Electrolytic Plasma Processing (EPP) prior to deposition. A "hill and valley" morphology was observed on the uppermost layer of the EPP-treated substrates. The microstructure and also roughness of the EPP-treated substrates were characterized by Scanning Electron Microscopy (SEM) and Profilometry. Similarly, the deposited TiO2 thin films were also characterized by SEM, Energy Dispersive Spectroscopy (EDS), Raman, Transmission Electron Microscopy (TEM), X-ray Diffractometry (XRD), and Profilometry. It was found that the PEO deposited film on titanium substrate was composed of anatase and the film on the aluminum substrate was amorphous. The average thickness of the PEO deposited films was about 6-10 microns. TiO2 thin films deposited by DC magnetron sputtering were found to be almost amorphous with an average thickness of 650 nm. High resolution TEM analysis showed some areas of crystallinity with a grain size of ~5 nm. Photoelectrocurrent measurements were then performed on all deposited films by a standard single-compartment, three-electrode electrochemical cell. It has been observed that the films deposited by PVD technique have a much higher quality and produce much higher photocurrent comparing to ones of PEO method.
Download or read book Surface Modifications and Growth of Titanium Dioxide for Photo Electrochemical Water Splitting written by John Alexander and published by Springer. This book was released on 2016-05-21 with total page 366 pages. Available in PDF, EPUB and Kindle. Book excerpt: This outstanding thesis provides a wide-ranging overview of the growth of titanium dioxide thin films and its use in photo-electrochemicals such as water splitting. The context for water splitting is introduced with the theory of semiconductor-liquid junctions, which are dealt with in detail. In particular plasmonic enhancement of TiO2 by the addition of gold nanoparticles is considered in depth, including a thorough and critical review of the literature, which discusses the possible mechanisms that may be at work. Plasmonic enhancement is demonstrated with gold nanoparticles on Nb-doped TiO2. Finally, the use of temperature and pressure to control the phase and morphology of thin films grown by pulsed laser deposition is presented.
Download or read book Titanium Dioxide Photocatalysis written by Vladimiro Dal Santo and published by MDPI. This book was released on 2019-05-27 with total page 208 pages. Available in PDF, EPUB and Kindle. Book excerpt: Although the seminal work of Fujishima et al. dates back to 1971, TiO2 still remains the most diffused and studied semiconductor, employed in photo-oxidation processes for cleantech (i.e., polluted water and air treatment), in solar fuel production (mainly hydrogen production by water photo splitting), and in Carbon Capture and Utilization (CCU) processes by CO2 photoreduction. The eleven articles, among them three reviews, in this book cover recent results and research trends of various aspects of titanium dioxide photocatalysis, with the chief aim of improving the final efficiency of TiO2-based materials. Strategies include doping, metal co-catalyst deposition, and the realization of composites with plasmonic materials, other semiconductors, and graphene. Photocatalysts with high efficiency and selectivity can be also obtained by controlling the precise crystal shape (and homogeneous size) and the organization in superstructures from ultrathin films to hierarchical nanostructures. Finally, the theoretical modeling of TiO2 nanoparticles is discussed and highlighted. The range of topics addressed in this book will stimulate the reader’s interest as well as provide a valuable source of information for researchers in academia and industry.
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 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 Titanium Dioxide written by Hafiz Muhammad Ali and published by BoD – Books on Demand. This book was released on 2022-03-02 with total page 246 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book presents a comprehensive overview of titanium dioxide, including recent advances and applications. It focuses on the compound’s uses in environmental remediation, photocatalytic materials, rechargeable lithium-ion batteries, thin films, energy storage, semiconductors, and much more. This volume is a useful resource for researchers, scientists, engineers, and students.
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 Chemistry of Ozone in Water and Wastewater Treatment written by Clemens von Sonntag and published by IWA Publishing. This book was released on 2012-08-31 with total page 306 pages. Available in PDF, EPUB and Kindle. Book excerpt: Even though ozone has been applied for a long time for disinfection and oxidation in water treatment, there is lack of critical information related to transformation of organic compounds. This has become more important in recent years, because there is considerable concern about the formation of potentially harmful degradation products as well as oxidation products from the reaction with the matrix components. In recent years, a wealth of information on the products that are formed has accumulated, and substantial progress in understanding mechanistic details of ozone reactions in aqueous solution has been made. Based on the latter, this may allow us to predict the products of as yet not studied systems and assist in evaluating toxic potentials in case certain classes are known to show such effects. Keeping this in mind, Chemistry of Ozone in Water and Wastewater Treatment: From Basic Principles to Applications discusses mechanistic details of ozone reactions as much as they are known to date and applies them to the large body of studies on micropollutant degradation (such as pharmaceuticals and endocrine disruptors) that is already available. Extensively quoting the literature and updating the available compilation of ozone rate constants gives the reader a text at hand on which his research can be based. Moreover, those that are responsible for planning or operation of ozonation steps in drinking water and wastewater treatment plants will find salient information in a compact form that otherwise is quite disperse. A critical compilation of rate constants for the various classes of compounds is given in each chapter, including all the recent publications. This is a very useful source of information for researchers and practitioners who need kinetic information on emerging contaminants. Furthermore, each chapter contains a large selection of examples of reaction mechanisms for the transformation of micropollutants such as pharmaceuticals, pesticides, fuel additives, solvents, taste and odor compounds, cyanotoxins. Authors: Prof. Dr. Clemens von Sonntag, Max-Planck-Institut für Bioanorganische Chemie, Mülheim an der Ruhr, and Instrumentelle Analytische Chemie, Universität Duisburg-Essen, Essen, Germany and Prof. Dr. Urs von Gunten, Eawag, Swiss Federal Institute of Aquatic Science and Technology, Dübendorf, and Ecole Polytechnique Federal de Lausanne, Lausanne, Switzerland.
Download or read book TiO2 Nanoparticles written by Aiguo Wu and published by John Wiley & Sons. This book was released on 2020-06-02 with total page 252 pages. Available in PDF, EPUB and Kindle. Book excerpt: A unique book that summarizes the properties, toxicology, and biomedical applications of TiO2-based nanoparticles Nanotechnology is becoming increasingly important for products used in our daily lives. Nanometer-sized titanium dioxide (TiO2) are widely used in industry for different purposes, such as painting, sunscreen, printing, cosmetics, biomedicine, and so on. This book summarizes the advances of TiO2 based nanobiotechnology and nanomedicine, covering materials properties, toxicological research, and biomedical application, such as antibacter, biosensing, and cancer theranostics. It uniquely integrates the TiO2 applications from physical properties, toxicology to various biomedical applications, and includes black TiO2 based cancer theranostics. Beginning with a comprehensive introduction to the properties and applications of nanoparticles, TiO2 Nanoparticles: Applications in Nanobiotechnology, Theranostics and Nanomedicine offers chapters on: Toxicity of TiO2 Nanoparticles; Antibacterial Applications of TiO2 Nanoparticles; Surface Enhanced Raman Spectrum of TiO2 Nanoparticle for Biosensing (TiO2 Nanoparticle Served as SERS Sensing Substrate); TiO2 as Inorganic Photosensitizer for Photodynamic Therapy; Cancer Theranostics of Black TiO2 Nanoparticles; and Neurodegenerative Disease Diagnostics and Therapy of TiO2-Based Nanoparticles. This title: -Blends the physical properties, toxicology of TiO2 nanoparticles to the many biomedical applications -Includes black TiO2 based cancer theranostics in its coverage -Appeals to a broad audience of researchers in academia and industry working on nanomaterials-based biosensing, drug delivery, nanomedicine TiO2 Nanoparticles: Applications in Nanobiotechnology, Theranostics and Nanomedicine is an ideal book for medicinal chemists, analytical chemists, biochemists, materials scientists, toxicologists, and those in the pharmaceutical industry.
Download or read book Enhancing the Photoelectrochemical Water Splitting Characteristics of Titanium and Tungsten Oxide Based Materials Via Doping and Sensitization written by Ruchi Gakhar and published by . This book was released on 2015 with total page 602 pages. Available in PDF, EPUB and Kindle. Book excerpt: To better utilize solar energy for clean energy production, efforts are needed to overcome the natural diurnal variation and the diffuse nature of sunlight. Photoelectrochemical (PEC) hydrogen generation by water splitting is a promising approach to harvest solar energy. Hydrogen gas is a clean and high energy capacity fuel. However, the solar-to-hydrogen conversion efficiency is determined mainly by the properties of the materials employed as photoanodes. Improving the power-conversion efficiency of PEC water splitting requires the design of inexpensive and efficient photoanodes that have strong visible light absorption, fast charge separation, and lower charge recombination rate. In the present study, PEC characteristics of various semiconducting photoelectrodes such as TiO2, WO3 and CuWO4 were investigated. Due to the inherent wide gap, such metal oxides absorb only ultraviolet radiation. Since ultraviolet radiation only composes of 4% of the sun's spectrum, the wide band gap results in lower charge collection and efficiency. Thus to improve optical absorption and charge separation, it is necessary to modify the band gap with low band gap materials.The two approaches followed for modification of band gap are doping and sensitization. Here, TiO2 and WO3 based photoanodes were sensitized with ternary quantum dots, while doping was the primary method utilized to investigate the modification of the band gap of CuWO4. The first part of this dissertation reports the synthesis of ternary quantum dot - sensitized titania nanotube array photoelectrodes. Ternary quantum dots with varying band gaps and composition (MnCdSe, ZnCdSe and CdSSe) were tethered to the surface of TiO2 nanotubes using successive ionic layer adsorption and reaction (SILAR) technique. The stoichiometry of ternary quantum dots was estimated to beMn0.095Cd0.95Se, Zn0.16Cd0.84Se and CdS0.54Se0.46. The effect of varying number of sensitization cycles and annealing temperature on optical and photoelectrochemical properties of prepared photoanodes were studied. The absorption properties and surface morphology of the sensitized tubes was analyzed using UV-visible spectroscopy and scanning electron microscopy. The phase composition was determined using X-Ray diffraction and X-ray photoelectron spectroscopy techniques. Electrodes were also evaluated for their stability using inductively coupled plasma optical emission spectrometry. Results show that the sensitization of TiO2 nanotubes with MnCdSe (8.79 mA/cm2), ZnCdSe (12.70 mA/cm2) and CdSSe (15.58 mA/cm2) resulted in up to a 30 fold increase in photocurrent compared to unsensitized nanotubes (0.4 mA/cm2). In the second part, the application of WO3 as photoanode for water splitting was explored. The porous thin films of WO3 films were sensitized with ternary quantum dots (ZnCdSe) using the SILAR technique. The structural, surface morphological and optical properties of the sensitized WO3 thin films were studied. PEC characteristics of the sensitized films were found to be 120 fold increase (8.53 mA/cm2) in comparison to that of unmodified WO3 films (0.07 mA/cm2). In the last part of this dissertation, CuWO4 was investigated as the potential photoanode material. The band gap of CuWO4 was estimated using density functional theory (DFT) calculations. The band structure was obtained using the first-principles plane wave self-consistent field (pwscf) method and the effect of nickel dopant on the band gap and optical properties of CuWO4 was evaluated. Theoretical calculations showed that doping led to a decrease in band gap. The validity of the theoretical approach was evaluated by experimentally synthesizing Ni-doped CuWO4 electrodes. Experimental results showed that the band gap indeed decreases when CuWO4 was doped with Ni, and thus validated the DFT approach. Ternary quantum dots were found to increase the PEC activity of TiO2 and WO3 based photoelectrodes by 120 fold. In addition, a method of computing band gap of semiconductor using DFT modeling was developed and validated with experimental results.
Download or read book Diamond Electrochemistry written by Akira Fujishima and published by Elsevier. This book was released on 2005 with total page 616 pages. Available in PDF, EPUB and Kindle. Book excerpt: Provides an overview of research in Diamond Electrochemistry, as well as practical applications of diamond electrodes. With chapters written by experts in their respective fields, this book serves as a useful source of information for electrochemists working in physical or analytical chemistry.
Download or read book Characterization of Solid Materials and Heterogeneous Catalysts written by Michel Che and published by John Wiley & Sons. This book was released on 2012-04-16 with total page 1313 pages. Available in PDF, EPUB and Kindle. Book excerpt: This two-volume book provides an overview of physical techniques used to characterize the structure of solid materials, on the one hand, and to investigate the reactivity of their surface, on the other. Therefore this book is a must-have for anyone working in fields related to surface reactivity. Among the latter, and because of its most important industrial impact, catalysis has been used as the directing thread of the book. After the preface and a general introduction to physical techniques by M. Che and J.C. Vedrine, two overviews on physical techniques are presented by G. Ertl and Sir J.M. Thomas for investigating model catalysts and porous catalysts, respectively. The book is organized into four parts: Molecular/Local Spectroscopies, Macroscopic Techniques, Characterization of the Fluid Phase (Gas and/ or Liquid), and Advanced Characterization. Each chapter focuses upon the following important themes: overview of the technique, most important parameters to interpret the experimental data, practical details, applications of the technique, particularly during chemical processes, with its advantages and disadvantages, conclusions.
Download or read book Photocatalytic Activity of TiO2 and V2O5 Thin Films written by Kody Bornstein 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 Chromium Doped TiO2 Sputtered Thin Films written by Anouar Hajjaji and published by Springer. This book was released on 2014-12-24 with total page 139 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book presents co-sputtered processes ways to produce chrome doped TiO2 thin films onto various substrates such as quartz, silicon and porous silicon. Emphasis is given on the link between the experimental preparation and physical characterization in terms of Cr content. Moreover, the structural, optical and optoelectronic investigations are emphasized throughout. The book explores the potencial applications of devices based on Cr doped TiO2 thin films as gas sensors and in photocatalysis and in the photovoltaic industry. Also, this book provides extensive leads into research literature, and each chapter contains details which aim to develop awareness of the subject and the methods used. The content presented here will be useful for graduate students as well as researchers in materials science, physics, chemistry and engineering.
Download or read book Nanostructured Titanium Dioxide in Photocatalysis written by It-Meng Low and published by CRC Press. This book was released on 2021-06-18 with total page 250 pages. Available in PDF, EPUB and Kindle. Book excerpt: Titanium dioxide (TiO2) has drawn considerable attention as an attractive inorganic raw material for various applications due to its inexpensiveness, nontoxic nature, stability, and excellent photocatalytic activity. Photocatalysis is one of the most promising route for sustainable chemistry of the 21st century. It can contribute to solving environmental, global energy, and chemical problems, as well as to the sustainable production of commodities in the near future. This book presents the fundamentals of photocatalysis in nanostructured TiO2 and describes the factors affecting the photocatalytic activity, design, and synthesis of various forms of nanostructured TiO2. It highlights the use of ion-doping and inert-atmosphere annealing to extend the light-absorption range of photocatalysts and reduce recombination between electrons and holes. It discusses numerous applications in the fields of energy and environment, such as water purification, gas sensing, storage and delivery, and energy generation. The book is an invaluable resource and useful guide for a broad readership in various fields of catalysis, materials science, environment, and energy.
Download or read book Nanostructured And Photoelectrochemical Systems For Solar Photon Conversion written by Mary D Archer and published by World Scientific. This book was released on 2008-08-04 with total page 781 pages. Available in PDF, EPUB and Kindle. Book excerpt: In this book, expert authors describe advanced solar photon conversion approaches that promise highly efficient photovoltaic and photoelectrochemical cells with sophisticated architectures on the one hand, and plastic photovoltaic coatings that are inexpensive enough to be disposable on the other. Their leitmotifs include light-induced exciton generation, junction architectures that lead to efficient exciton dissociation, and charge collection by percolation through mesoscale phases. Photocatalysis is closely related to photoelectrochemistry, and the fundamentals of both disciplines are covered in this volume./a
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.
