Download or read book Atomic Level Study of Structural Changes of TiO2 Based Photocatalysts During Solar Water Splitting Reactions Using TEM written by Liuxian Zhang and published by . This book was released on 2015 with total page 156 pages. Available in PDF, EPUB and Kindle. Book excerpt: Photocatalytic water splitting is a promising technique to produce H2 fuels from water using sustainable solar energy. To better design photocatalysts, the understanding of charge transfer at surfaces/interfaces and the corresponding structure change during the reaction is very important. Local structural and chemical information on nanoparticle surfaces or interfaces can be achieved through characterizations on transmission electron microscopy (TEM). Emphasis should be put on materials structure changes during the reactions in their "working conditions". Environmental TEM with in situ light illumination system allows the photocatalysts to be studied under light irradiation when exposed to H2O vapor. A set of ex situ and in situ TEM characterizations are carried out on typical types of TiO2 based photocatalysts. The observed structure changes during the reaction are correlated with the H2 production rate for structure-property relationships. A surface disordering was observed in situ when well-defined anatase TiO2 rhombohedral nanoparticles were exposed to 1 Torr H2O vapor and 10suns light inside the environmental TEM. The disordering is believed to be related to high density of hydroxyl groups formed on surface oxygen vacancies during water splitting reactions.Pt co-catalyst on TiO2 is able to split pure water producing H2 and O2. The H2 production rate drops during the reaction. Particle size growth during reaction was discovered with Z-contrast images. The particle size growth is believed to be a photo-electro-chemical Ostwald ripening. Characterizations were also carried out on a more complicated photocatalyst system: Ni/NiO core/shell co-catalyst on TiO2. A decrease of the H2 production rate resulting from photo-corrosion was observed. The Ni is believed to be oxidized to Ni2+ by OH radicals which are intermediate products of H2O oxidation. The mechanism that the OH radicals leak into the cores through cracks on NiO shells is more supported by experiments. Overall this research has done a comprehensive ex situ and in situ TEM characterizations following some typical TiO2 based photocatalysts during reactions. This research has shown the technique availability to study photocatalyst inside TEM in photocatalytic conditions. It also demonstrates the importance to follow structure changes of materials during reactions in understanding deactivation mechanisms.
Download or read book TiO2 Photocatalysis written by Akira Fujishima and published by . This book was released on 1999 with total page 176 pages. Available in PDF, EPUB and Kindle. Book excerpt:
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 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 Sustainable Energy Systems and Applications written by Ibrahim Dincer and published by Springer Science & Business Media. This book was released on 2011-11-05 with total page 823 pages. Available in PDF, EPUB and Kindle. Book excerpt: The concept of sustainable development was first introduced by the Brundtland Commission almost 20 years ago and has received increased attention during the past decade. It is now an essential part of any energy activities. This is a research-based textbook which can be used by senior undergraduate students, graduate students, engineers, practitioners, scientists, researchers in the area of sustainable energy systems and aimed to address some key pillars: better efficiency, better cost effectiveness, better use of energy resources, better environment, better energy security, and better sustainable development. It also includes some cutting-edge topics, such hydrogen and fuel cells, renewable, clean combustion technologies, CO2 abatement technologies, and some potential tools (exergy, constructal theory, etc.) for design, analysis and performance improvement.
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 2D Metal Carbides and Nitrides MXenes written by Babak Anasori and published by Springer Nature. This book was released on 2019-10-30 with total page 534 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book describes the rapidly expanding field of two-dimensional (2D) transition metal carbides and nitrides (MXenes). It covers fundamental knowledge on synthesis, structure, and properties of these new materials, and a description of their processing, scale-up and emerging applications. The ways in which the quickly expanding family of MXenes can outperform other novel nanomaterials in a variety of applications, spanning from energy storage and conversion to electronics; from water science to transportation; and in defense and medical applications, are discussed in detail.
Download or read book Solid State Chemistry and Photocatalysis of Titanium Dioxide written by Maria K. Nowotny and published by Trans Tech Publications Ltd. This book was released on 2010-06-07 with total page 360 pages. Available in PDF, EPUB and Kindle. Book excerpt: Volume is indexed by Thomson Reuters BCI (WoS). The goal of this special volume was to provide a unique opportunity to exchange information, to present the latest results and to review relevant issues affecting contemporary diffusion research. The large number (over 232) of peer-reviewed papers emphasizes the considerable academic and industrial interest in this field.
Download or read book Photocatalytic Hydrogen Evolution written by Misook Kang and published by MDPI. This book was released on 2020-06-17 with total page 136 pages. Available in PDF, EPUB and Kindle. Book excerpt: Energy crises and global warming pose serious challenges to researchers in their attempt to develop a sustainable society for the future. Solar energy conversion is a remarkable, clean, and sustainable way to nullify the effects of fossil fuels. The findings of photocatalytic hydrogen production (PCHP) by Fujishima and Honda propose that “water will be the coal for the future”. Hydrogen is a carbon-free clean fuel with a high specific energy of combustion. Titanium oxide (TiO2), graphitic-carbon nitride (g-C3N4) and cadmium sulfide (CdS) are three pillars of water splitting photocatalysts owing to their superior electronic and optical properties. Tremendous research efforts have been made in recent years to fabricate visible or solar-light, active photocatalysts. The significant features of various oxide, sulfide, and carbon based photocatalysts for cost-effective hydrogen production are presented in this Special Issue. The insights of sacrificial agents on the hydrogen production efficiency of catalysts are also presented in this issue.
Download or read book Hierarchical Nanostructures for Energy Devices written by Seung H Ko and published by Royal Society of Chemistry. This book was released on 2014-10-29 with total page 323 pages. Available in PDF, EPUB and Kindle. Book excerpt: Surface area has a directly relationship with the efficiency of energy devices. Hierarchical nanostructuring has the potential to greatly increase surface area, and their electrical properties are favourable, not only to energy generation and storage, but also energy-consuming electronic circuits. This book provides systematic coverage of how nanostructured materials can be applied to energy devices, with an emphasis on the process of generation to storage and consumption. The fundamentals (including properties, characterisation and synthesis) are clearly presented across the first chapters of the book, providing readers new to the field with a clear overview of this expanding topic. The detailed discussion of applications will be an inspiration to those already well-versed in the field. The editors have more than a decade of experience in working on all aspects of energy generation and storage - in academia, national laboratories and industry. The book presents a balanced view from all sectors and is presented in a format accessible by postgraduate students and professional researchers alike.
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 Visible Light Self Supported TiO2 Based Photocatalysts written by Fateh Mikaeili and published by . This book was released on 2021 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Rapid population growth and ever-increasing energy consumption have resulted in increased environmental pollution and energy demands in recent years. Accordingly, studies and research on innovative and efficient ways of wastewater clean-up and exploiting eco-friendly and renewable energy sources such as sunlight have become a necessity. This dissertation focuses on the nanostructured TiO2 system as a visible light photocatalyst and an agent for water splitting. Effects of (i) Polymorphism, (ii) Dopant, and (iii) Morphology on the photocatalytic properties of the material were studied by using methylene blue as the degrading component. Then the polymorphic stability between Sol-Gel and Electrospun mats was studied. Brook, which is the least studied polymorph of TiO2, showed the highest impact on improving the photocatalytic activity when mixed with Anatase as opposed to Rutile. Brookite is then confirmed to be a desirable polymorph for the Titania system. Brookite stabilization was found to be dependent on dopant (Copper) for a very distinct range of concentration and the processing route employed. Sol-Gel Processed Titania didn’t show any Brookite in the pure state upon heat treatment where electrospun Titania using the same sol-gel precursor did, in fact so showed the presence of Brookite in the temperature range of 500-550c. In-Situ studies in electron microscope confirmed this finding. Emphasis was then paid to the electrospinning process as it controls the morphology and properties of the self-supported nanocrystalline grids of TiO2 photocatalysts. Changes in the properties of the carrier polymer were observed as a function of this electrostatic processing. Later, Cellulose Acetate processed mats were confirmed to depict super water-repellant properties, and the underlying mechanism behind the shift from hydrophilicity to the hydrophobicity of these mats was studied. From the engineering point of view, having hybrids of CA mats and Photocatalytic TiO2 Nanogrids will produce the photocatalyst and water splitting agents of the future.
Download or read book Emerging Trends in TiO2 Photocatalysis and Applications written by Trong-On Do and published by MDPI. This book was released on 2020-12-28 with total page 596 pages. Available in PDF, EPUB and Kindle. Book excerpt: The semiconductor titanium dioxide (TiO2) has been evolved as a prototypical material to understand the photocatalytic process, and has been demonstrated for various photocatalytic applications such as pollutants degradation, water splitting, heavy metal reduction, CO2 conversion, N2 fixation, bacterial disinfection, etc. Rigorous photocatalytic studies on TiO2 have paved the way to understanding the various chemical processes involved and the physical parameters (optical and electrical) required to design and construct diverse photocatalytic systems. Accordingly, it has been realized that an effective photocatalyst should have ideal band edge potential, narrow band gap energy, reduced charge recombination, enhanced charge separation, improved interfacial charge transfer, surface-rich catalytic sites, etc. As a result, many strategies have been developed to design a variety of photocatalytic systems, which include doping, composite formation, sensitization, co-catalyst loading, etc. Towards highlighting the above-mentioned diversities in TiO2 photocatalysis, there have been many interesting original research works on TiO2, involving material designs for various photocatalytic applications published in this Special Issue. In addition, some excellent review papers have also been published in this Special Issue, focusing on the various TiO2-based photocatalytic systems and their mechanisms and applications.
Download or read book Photo generated Electrons in TiO2 Properties Behaviors Reactions and Applications written by Jiawei Liu and published by . This book was released on 2018 with total page 200 pages. Available in PDF, EPUB and Kindle. Book excerpt: Titanium dioxide (TiO2) and TiO2-based materials are one of the most promising photocatalysts known today due to its stable, widespread, low-cost properties and suitable band position. Since the first discovery of TiO2's photocatalytic activity in 1972, it has been extensively studied for the application in solar energy utilization, including solar cell, waste water/VOCs control, hydrogen production, and photocatalytic conversion of solar energy to chemical energy (artificial photosynthesis). Despite the fact that TiO2 and TiO2-based photocatalysts suffer the disadvantages of wide band gap and relatively slow reaction rate, many applications have been available on market such as the UV/TiO2 indoor air purifier, self-cleaning coatings, and solar cells. In order to further improve the performance, the fundamental research of the mechanism and reaction pathways have attracted much attention on the steps of photoexcitation, the subsequent diffusion and accumulation of charges, and the photoreduction/oxidation reactions. In this dissertation, the accumulation and diffusion of photo-generated conduction-band electrons (e-CB) and shallow-trap electrons (e-ST), which are considered as key steps in photocatalysis, is studied in detail with the help of in situ Infrared (IR) techniques. e-CB was produced by light faster than e-ST, and then injected to the trap sites. N-doping onto TiO2 produced a higher population of e-ST and generated e-ST and e-CB at a lower rate than TiO2. The average energy level of e-ST was determined to be 0.30 eV for TiO2 and 0.26 eV for N-TiO2 below the conduction band. Comparison study of 5 organic hole scavengers on TiO2 illustrates the critical correlation of photo-generated electrons with two key chemical bonds: (i) e-ST influences the surface electrical field, leading to the Stark effect (C-H), and (ii) e-CB fills in the Ti 3d orbitals, which reversibly breaks Ti-O bonds. The tunability of photo-generated electrons and reaction pathways by organic hole scavengers were achieved, leading to different final products. Finally, the study of photo-generated electrons in TiO2 and N-TiO2 Dye-sensitized Solar Cell (DSSC) suggests that nitrogen (N-) doping on TiO2 blocked linear OH, exhibiting a more hydrophobic surface characteristic than undoped TiO2. N-doping further increased the electron-hole separation by solar light on working electrode and the current density in the DSSC.We hope this systematic study on photo-generated electrons will shed light on the understanding of fundamental photocatalytic processes and be beneficial for the future design of catalysts, devices, and processes.
Download or read book Introduction to Photocatalysis written by Yoshio Nosaka and published by Royal Society of Chemistry. This book was released on 2019-03-07 with total page 272 pages. Available in PDF, EPUB and Kindle. Book excerpt: Presenting the basic science of semiconductor photocatalysis together with the various practical applications, this textbook is ideal for graduate students. It covers fundamental principles and applicable techniques of light, solid state physics, electrochemistry, reaction kinetics, and materials processing. A solid understanding of semiconductor photoelectrochemistry is developed through discussing the basic properties of a representative photocatalytic material, TiO2; the basic science of the light absorption phenomenon and the application to the powder suspension useful for the photocatalytic research; and the electronic state of semiconductors. Following this, the textbook moves on to explore photoelectrochemistry; the mechanism and kinetic analysis of photocatalytic reactions; typical fabrication methods of common photocatalysts and the factors for improving photocatalytic activity; and evaluation methods of photocatalytic activity. The textbook concludes by looking at the future prospects of the applications of photocatalysis. This introductory textbook provides a foundation in photocatalysis to supplement graduate courses in catalysis, environmental science, materials science and chemical engineering.
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 Surface Science of Photocatalysis written by Jiaguo Yu and published by Academic Press. This book was released on 2020-04-14 with total page 602 pages. Available in PDF, EPUB and Kindle. Book excerpt: Surface Science of Photocatalysis, Volume 32, summarizes significant findings on the surface science behind various classic and novel photocatalysts for energy and environmental applications, with special emphasis on important surface/interface processes in photocatalysis, such as interfacial charge transfer, function of co-catalysts, and adsorption over photocatalyst surface. This book timely and systematically reviews the state-of-the-art of the surface science in semiconductor-based photocatalysis, serving as a useful reference book for both new and experienced researchers in this field. Provides timely reviews on cutting-edge research on surface science and photocatalysts Comprehensively discusses novel photocatalysts, such as metal oxides, metal sulphides, graphitic carbon nitrides, graphene and metal-organics Presents important surface/interface processes in photocatalysis, like Z-scheme system and surface heterojunctions Investigates the function of co-catalysts and the adsorption on photocatalyst surfaces Edited by world-leading researchers in interface science
