Download or read book Understanding and Improving Hydrogen Storage Materials with Density Functional Theory Methods written by Evan Welchman and published by . This book was released on 2017 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: This work outlines some of the current issues driving the development of methods for using hydrogen as an energy carrier. I argue that suitably storing hydrogen is the key technological challenge to this effort. I describe the technical requirements for what constitutes a suitable hydrogen storage material and explain the three primary mechanisms by which these materials can operate. In many cases, the relevant physical and electronic properties of these materials can be modeled computationally with density functional theory, and I describe some of the myriad assumptions and methods necessary to do that. I successfully apply that formalism to study both chemical and adsorption-based hydrogen storage materials. In NH3BH3 (ammonia borane or AB), I explain the cause of experimentally-observed disorder. I also propose improving the material's hydrogen storage properties by switching out one hydridic hydrogen atom with Cu. In metal borohydrides and metal borohydride ammoniates, I more fully describe how decomposition mechanisms change after ammoniation, and propose a new decomposition mechanism for a subset of these materials. Moving on to study adsorption-based storage as well, I fully characterize the crystal structure and bonding of a high-pressure mix of AB and H2 (the most hydrogen-dense material fully characterized in the literature to date), and describe a general scheme that could be used to characterize other hydrogen-dense materials. I also assist in proposing a novel decoration to the organic linkers in Zn-MOF-74 that would quintuple the material's hydrogen storage capacity and suggesting a new class of hydrogen storage materials based on alkane chains.
Download or read book Hydrogen Storage Materials written by R. G. Barnes and published by . This book was released on 1988 with total page 336 pages. Available in PDF, EPUB and Kindle. Book excerpt: Ames Laboratory, Iowa, USA
Download or read book The Investigation of Hydrogen Storage Material Design by Density Functional Theory A Case Study of Amorphous Carbon written by 陳映澄 and published by . This book was released on 2022 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Theoretical and Experimental Study of Solid State Complex Borohydride Hydrogen Storage Materials written by Pabitra Choudhury and published by . This book was released on 2009 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: ABSTRACT: Materials that are light weight, low cost and have high hydrogen storage capacity are essential for on-board vehicular applications. Some reversible complex hydrides are alanates and amides but they have lower capacity than the DOE target (6.0 wt %) for 2010. High capacity, light weight, reversibility and fast kinetics at lower temperature are the primary desirable aspects for any type of hydrogen storage material. Borohydride complexes as hydrogen storage materials have recently attracted great interest. Understanding the above parameters for designing efficient complex borohydride materials requires modeling across different length and time scales. A direct method lattice dynamics approach using ab initio force constants is utilized to calculate the phonon dispersion curves. This allows us to establish stability of the crystal structure at finite temperatures. Density functional theory (DFT) is used to calculate electronic properties and the direct method lattice dynamics is used to calculate the finite temperature thermodynamic properties. These computational simulations are applied to understand the crystal structure, nature of bonding in the complex borohydrides and mechanistic studies on doping to improve the kinetics and reversibility, and to improve the hydrogen dynamics to lower the decomposition temperature. A combined theoretical and experimental approach can better lead us to designing a suitable complex material for hydrogen storage. To understand the structural, bulk properties and the role of dopants and their synergistic effects on the dehydrogenation and/or reversible rehydrogenation characteristics, these complex hydrides are also studied experimentally in this work.
Download or read book Density Functional Theory written by David S. Sholl and published by John Wiley & Sons. This book was released on 2011-09-20 with total page 252 pages. Available in PDF, EPUB and Kindle. Book excerpt: Demonstrates how anyone in math, science, and engineering can master DFT calculations Density functional theory (DFT) is one of the most frequently used computational tools for studying and predicting the properties of isolated molecules, bulk solids, and material interfaces, including surfaces. Although the theoretical underpinnings of DFT are quite complicated, this book demonstrates that the basic concepts underlying the calculations are simple enough to be understood by anyone with a background in chemistry, physics, engineering, or mathematics. The authors show how the widespread availability of powerful DFT codes makes it possible for students and researchers to apply this important computational technique to a broad range of fundamental and applied problems. Density Functional Theory: A Practical Introduction offers a concise, easy-to-follow introduction to the key concepts and practical applications of DFT, focusing on plane-wave DFT. The authors have many years of experience introducing DFT to students from a variety of backgrounds. The book therefore offers several features that have proven to be helpful in enabling students to master the subject, including: Problem sets in each chapter that give readers the opportunity to test their knowledge by performing their own calculations Worked examples that demonstrate how DFT calculations are used to solve real-world problems Further readings listed in each chapter enabling readers to investigate specific topics in greater depth This text is written at a level suitable for individuals from a variety of scientific, mathematical, and engineering backgrounds. No previous experience working with DFT calculations is needed.
Download or read book Fueling the Future written by United States. Congress. House. Committee on Science. Subcommittee on Energy and published by . This book was released on 2006 with total page 376 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Density Functional Theory DFT Study of Hydrogen Storage in Porous Silicon written by Mawla Boaks and published by . This book was released on 2018 with total page 136 pages. Available in PDF, EPUB and Kindle. Book excerpt: Based on plane wave DFT calculation, we carried out micro level investigation of hydrogen storage in nanoporous silicon (npSi). One quarter of a hexagonal pore with Palladium catalyst placed at the surface has been studied for hydrogen dissociation, spillover, bond hopping, and diffusion for both single catalyst atom and small catalyst cluster consisting of multiple catalyst atoms. All the DFT computations were done in one of the biggest research supercomputer facilities of the world, Big Red II. We opted ABINIT, an open source DFT tool for our computations. Our calculation revealed low dissociation, spillover, and bond hoping energy barrier. The energy required to be provided from external sources to fully recharge the storage medium from a gaseous source at a completely empty state has also been evaluated. Hydrogen diffusion along the inner surface of the pore as a means of bond hopping and the possibility of quantum tunneling, a low temperature phenomena used to spontaneously go over an otherwise less likely high energy barrier have been studied as well. Using these micro level parameter values evaluated from the DFT study, the performance of any potential hydrogen storage material can be compared to a set of characteristics sought in an efficient storage media. Thus, the micro scale feasibility of this novel npSi material based hydrogen storage technology was studied as a part of a STTR Phase I project.
Download or read book Solid State Hydrogen Storage written by Gavin Walker and published by Woodhead Publishing. This book was released on 2008-09-30 with total page 616 pages. Available in PDF, EPUB and Kindle. Book excerpt: Hydrogen fuel cells are emerging as a major alternative energy source in transportation and other applications. Central to the development of the hydrogen economy is safe, efficient and viable storage of hydrogen. Solid-state hydrogen storage: Materials and chemistry reviews the latest developments in solid-state hydrogen storage. Part one discusses hydrogen storage technologies, hydrogen futures, hydrogen containment materials and solid-state hydrogen storage system design. Part two reviews the analysis of hydrogen interactions including structural characterisation of hydride materials, neutron scattering techniques, reliably measuring hydrogen uptake in storage materials and modelling of carbon-based materials for hydrogen storage. Part three analyses physically-bound hydrogen storage with chapters on zeolites, carbon nanostructures and metal-organic framework materials. Part four examines chemically-bound hydrogen storage including intermetallics, magnesium hydride, alanates, borohydrides, imides and amides, multicomponent hydrogen storage systems, organic liquid carriers, indirect hydrogen storage in metal ammines and technological challenges in hydrogen storage. With its distinguished editor and international team of contributors, Solid-state hydrogen storage: Materials and chemistry is a standard reference for researchers and professionals in the field of renewable energy, hydrogen fuel cells and hydrogen storage. Assesses hydrogen fuel cells as a major alternative energy source Discusses hydrogen storage technologies and solid-state hydrogen storage system design Explores the analysis of hydrogen interactions including reliably measuring hydrogen uptake in storage materials
Download or read book Density Functional Theory Studies of Destabilized Metal Hydrides for Hydrogen Storage Applications written by Sudhakar Venkata Alapati and published by . This book was released on 2007 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book MXenes Fundamentals and Applications written by Inamuddin and published by Materials Research Forum LLC. This book was released on 2019-06-25 with total page 224 pages. Available in PDF, EPUB and Kindle. Book excerpt: This is the very first book on the highly promising topic of MXenes; focusing on their fundamental characteristics and properties, fabrication techniques and applications. MXenes are two-dimensional materials consisting of few atoms thick layers of transition metal carbides or nitrides. These are characterized by high electrical conductivity, good hydrophilicity, chemical stability, and ultrathin 2D sheet-like morphology. Applications in the energy, environmental, biomedical and electronic industries include catalysis, membrane separation, supercapacitors, hybrid-ion capacitors, batteries, flexible electronics, hydrogen storage, nanoelectronics, and sensors.
Download or read book Handbook of Hydrogen Storage written by Michael Hirscher and published by John Wiley & Sons. This book was released on 2010-04-26 with total page 388 pages. Available in PDF, EPUB and Kindle. Book excerpt: Owing to the limited resources of fossil fuels, hydrogen is proposed as an alternative and environment-friendly energy carrier. However, its potential is limited by storage problems, especially for mobile applications. Current technologies, as compressed gas or liquefied hydrogen, comprise severe disadvantages and the storage of hydrogen in lightweight solids could be the solution to this problem. Since the optimal storage mechanism and optimal material have yet to be identified, this first handbook on the topic provides an excellent overview of the most probable candidates, highlighting both their advantages as well as drawbacks. From the contents: ¿ Physisorption ¿ Clathrates ¿ Metal hydrides ¿ Complex hydrides ¿ Amides, imides, and mixtures ¿ Tailoring Reaction Enthalpies ¿ Borazan ¿ Aluminum hydride ¿ Nanoparticles A one-stop reference on all questions concerning hydrogen storage for physical and solid state chemists, materials scientists, chemical engineers, and physicists.
Download or read book fueling the future on the road to the hydrogen economy written by and published by DIANE Publishing. This book was released on with total page 366 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book DFT Study of Hydrogen Storage in Complex Hydrides Doped with Transition Metals written by Jiamei Yu and published by . This book was released on 2009 with total page 70 pages. Available in PDF, EPUB and Kindle. Book excerpt: In this thesis, two types of complex hydrides doped with transition metals as potential hydrogen storage materials were investigated using density functional theory (DFT) calculations. TiAl3 cluster as well as its interaction with hydrogen was characterized.
Download or read book Nanomaterials for Hydrogen Storage Applications written by Fatih Şen and published by Elsevier. This book was released on 2020-09-09 with total page 286 pages. Available in PDF, EPUB and Kindle. Book excerpt: Nanomaterials for Hydrogen Storage Applications introduces nanomaterials and nanocomposites manufacturing and design for hydrogen storage applications. The book covers the manufacturing, design, characterization techniques and hydrogen storage applications of a range of nanomaterials. It outlines fundamental characterization techniques for nanocomposites to establish their suitability for hydrogen storage applications. Offering a sound knowledge of hydrogen storage application of nanocomposites, this book is an important resource for both materials scientists and engineers who are seeking to understand how nanomaterials can be used to create more efficient energy storage solutions. - Assesses the characterization, design, manufacture and application of different types of nanomaterials for hydrogen storage - Outlines the major challenges of using nanomaterials in hydrogen storage - Discusses how the use of nanotechnology is helping engineers create more effective hydrogen storage systems
Download or read book Hydrogen Storage Materials written by R.G. Barnes and published by Trans Tech Publications Ltd. This book was released on 1988-01-01 with total page 332 pages. Available in PDF, EPUB and Kindle. Book excerpt: Materials Science Forum Vol. 31
Download or read book Final Report written by and published by . This book was released on 2011 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Hydrogen is a promising energy source for the future economy due to its environmental friendliness. One of the important obstacles for the utilization of hydrogen as a fuel source for applications such as fuel cells is the storage of hydrogen. In the infrastructure of the expected hydrogen economy, hydrogen storage is one of the key enabling technologies. Although hydrogen possesses the highest gravimetric energy content (142 KJ/g) of all fuels, its volumetric energy density (8 MJ/L) is very low. It is desired to increase the volumetric energy density of hydrogen in a system to satisfy various applications. Research on hydrogen storage has been pursed for many years. Various storage technologies, including liquefaction, compression, metal hydride, chemical hydride, and adsorption, have been examined. Liquefaction and high pressure compression are not desired due to concerns related to complicated devices, high energy cost and safety. Metal hydrides and chemical hydrides have high gravimetric and volumetric energy densities but encounter issues because high temperature is required for the release of hydrogen, due to the strong bonding of hydrogen in the compounds. Reversibility of hydrogen loading and unloading is another concern. Adsorption of hydrogen on high surface area sorbents such as activated carbon and organic metal frameworks does not have the reversibility problem. But on the other hand, the weak force (primarily the van der Waals force) between hydrogen and the sorbent yields a very small amount of adsorption capacity at ambient temperature. Significant storage capacity can only be achieved at low temperatures such as 77K. The use of liquid nitrogen in a hydrogen storage system is not practical. Perhydrides are proposed as novel hydrogen storage materials that may overcome barriers slowing advances to a hydrogen fuel economy. In conventional hydrides, e.g. metal hydrides, the number of hydrogen atoms equals the total valence of the metal ions. One LiH molecule contains one hydrogen atom because the valence of a Li ion is +1. One MgH2 molecule contains two hydrogen atoms because the valence of a Mg ion is +2. In metal perhydrides, a molecule could contain more hydrogen atoms than expected based on the metal valance, i.e. LiH1+n and MgH2+n (n is equal to or greater than 1). When n is sufficiently high, there will be plenty of hydrogen storage capacity to meet future requirements. The existence of hydrogen clusters, Hn+ (n = 5, 7, 9, 11, 13, 15) and transition metal ion-hydrogen clusters, M+(H2)n (n = 1-6), such as Sc(H2)n+, Co(H2)n+, etc., have assisted the development of this concept. Clusters are not stable species. However, their existence stimulates our approach on using electric charges to enhance the hydrogen adsorption in a hydrogen storage system in this study. The experimental and modeling work to verify it are reported here. Experimental work included the generation of cold hydrogen plasma through a microwave approach, synthesis of sorbent materials, design and construction of lab devices, and the determination of hydrogen adsorption capacities on various sorbent materials under various electric field potentials and various temperatures. The results consistently show that electric potential enhances the adsorption of hydrogen on sorbents. NiO, MgO, activated carbon, MOF, and MOF and platinum coated activated carbon are some of the materials studied. Enhancements up to a few hundred percents have been found. In general, the enhancement increases with the electrical potential, the pressure applied, and the temperature lowered. Theoretical modeling of the hydrogen adsorption on the sorbents under the electric potential has been investigated with the density functional theory (DFT) approach. It was found that the interaction energy between hydrogen and sorbent is increased remarkably when an electric field is applied. This increase of binding energy offers a potential solution for DOE when looking for a compromise between chemisorption and physisorption for hydrogen storage. Bonding of chemisorption is too strong and requires high temperature for the release of hydrogen. Bonding for the physisorption is too weak for sufficient uptake of hydrogen. Electric field potentials can enhance the physisorption and can be adjusted to yield reversibility required in a system at room temperature.
Download or read book Photoelectrochemical Hydrogen Generation written by Praveen Kumar and published by Springer Nature. This book was released on 2022-01-19 with total page 301 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book describes the hydrogen fuel generation from water via photoelectrochemical process. It elaborates the theory and fundamental concepts of photoelectrochemistry to understand the photoelectrochemical process for water splitting to generate hydrogen fuel. The book further deliberates about the hydrogen as a futuristic chemical fuel to store solar energy in the form of chemical bonds and also as a renewable alternative to fossil fuels. The book establishes the need for hydrogen fuel and discusses the standards and practices used for solar driven photoelectrochemical water splitting. It also discusses the current and future status of the nanomaterials as efficient photoelectrodes for solar photoelectrochemical water splitting. The book will be of interest to the researchers, students, faculty, scientists, engineers, and technologists working in the domain of material science, energy harvesting, energy conversion, photo electrochemistry, nanomaterials for photo-electrochemical (PEC) cell, etc.
