Download or read book Investigation of Hydrogen Storage in Single Walled Carbon Nanotubes for Fuel Cells 2 written by and published by . This book was released on 2010 with total page 15 pages. Available in PDF, EPUB and Kindle. Book excerpt: Single walled carbon nanotubes (SWCNTs) dispersed in 2-propanol are deposited on the alumina substrate using drop caste method. The deposited SWCNTs are characterized using the techniques SEM, EDS and FTIR. Then the SWCNTs are functionalized with BH3 using LiBH4 as the precursor. FTIR, XPS and CHNS techniques are use to confirm the functionalization. The functional groups are identified from FTIR studies. The various elements present in the functionalized SWCNTs are identified from XPS and CHNS studies. The functionalized samples are hydrogenated and the hydrogen storage capacity of these samples is estimated. The SWCNT deposition, functionalization with BH3 and hydrogenation are carried out successfully for the first time. The SWCNTs have been successfully functionalized with BH3 as predicted theoretically using LiBH4 as the precursor. From XPS studies, the presence of Li, B, and O are observed in our sample. Presence of BH3 is confirmed using FTIR studies. The hydrogen storage capacity of the functionalized SWCNTs is found to be 1.5 wt% at 50 deg C. Hydrogenation depends upon various parameters which are to be optimized to achieve maximum hydrogen storage capacity.

Download or read book Hydrogen Storage in Carbon Nanotubes at High Pressures LDRD Final Report 03 ERD 047 written by and published by . This book was released on 2004 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: This goal of this project was to perform feasibility experiments and measurements of the fundamental interactions between hydrogen and single wall carbon nanotubes (SWNT) at high pressures. High-pressure is an adjustable experimental parameter for tuning interaction strengths, thereby elucidating and providing insights into the fundamental nature of the H2/SWNT system. We have developed and utilized systems and methodologies to make x-ray scattering, optical spectroscopic and electrical transport measurements. These activities have been productive in demonstrating capabilities and measuring properties of SWNTs under high-pressure conditions. We have also developed strong cooperative and complementary relationships with academic research colleagues at Stanford University. Building on these results and relationships, we hope to continue and expand our research as co-investigators in a joint Harvard-LLNL-Stanford proposal to the DOE ''Grand Challenge'' for Basic and Applied Research in Hydrogen Storage (Solicitation No. DE-PS36-03GO93013). Hydrogen storage is an active research topic with important basic science implications and a crucial enabling technology for advanced energy systems. Measurements of the H2 storage capacity indicate that it may achieve or exceed the storage capacity level (6.5 wt-%) mandated by the DOE hydrogen plan for fielding a hydrogen-fueled vehicle. The H2/SWNT system has been the subject of intensive study and controversy regarding this storage capacity, with various conflicting measurements ranging from 1 wt-% up to values exceeding 7 wt-%[1-5]. The mechanism and details of the hydrogen storage in SWNT systems is poorly understood and several key questions have not been definitively determined including: (1) importance of SWNT structural parameters (tube length, diameter, end termination, bundling); (2) adsorption sites, mechanism, and binding energy; and (3) optimal storage capacity and conditions. This project sought to demonstrate techniques to address these key issues using high-pressure methodologies. Applying high-pressure conditions leads to an enhancement of the interaction between the hydrogen and the SWNTs. We use this capability in combination with optical, x-ray and electrical transport diagnostics to study the lattice parameters, vibrational energies, and electrical properties of hydrogen, SWNTs and the H2/SWNT system. Additionally high-pressure/low-temperature conditions allow us to immerse SWNT samples in liquid hydrogen, thereby maximizing the hydrogen uptake. Specifically, we directed efforts at developing a high-pressure cell for electric transport measurements, a cryostat for loading liquid hydrogen and optical studies SWNTs in high-pressure diamond anvil cells (DACs), and x-ray scattering experiments to measure SWNT structural and packing parameters.

Download or read book Green Synthesis of Nanomaterials for Bioenergy Applications written by Neha Srivastava and published by John Wiley & Sons. This book was released on 2020-11-09 with total page 266 pages. Available in PDF, EPUB and Kindle. Book excerpt: An authoritative summary of the quest for an environmentally sustainable synthesis process of nanomaterials and their application for environmental sustainability Green Synthesis of Nanomaterials for Bioenergy Applications is an important guide that provides information on the fabrication of nanomaterial and the application of low cost, green methods. The book also explores the impact on various existing bioenergy approaches. Throughout the book, the contributors—noted experts on the topic—offer a reliable summary of the quest for an environmentally sustainable synthesis process of nanomaterials and their application to the field of environmental sustainability. The green synthesis of nanoparticles process has been widely accepted as a promising technique that can be applied to a variety of fields. The green nanotechnology-based production processes to fabricate nanomaterials operates under green conditions without the intervention of toxic chemicals. The book’s exploration of more reliable and sustainable processes for the synthesis of nanomaterials, can lead to the commercial application of the economically viability of low-cost biofuels production. This important book: Summarizes the quest for an environmentally sustainable synthesis process of nanomaterials for their application to the field of environmental sustainability Offers an alternate, sustainable green energy approach that can be commercially implemented worldwide Covers recent approaches such as fabrication of nanomaterial that apply low cost, green methods and examines its impact on various existing bioenergy applications Written for researchers, academics and students of nanotechnology, nanosciences, bioenergy, material science, environmental sciences, and pollution control, Green Synthesis of Nanomaterials for Bioenergy Applications is a must-have guide that covers green synthesis and characterization of nanomaterials for cost effective bioenergy applications.

Download or read book Optimizing the Binding Energy of Hydrogen on Nanostructured Carbon Materials Through Structure Control and Chemical Doping written by and published by . This book was released on 2011 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The DOE Hydrogen Sorption Center of Excellence (HSCoE) was formed in 2005 to develop materials for hydrogen storage systems to be used in light-duty vehicles. The HSCoE and two related centers of excellence were created as follow-on activities to the DOE Office of Energy Efficiency and Renewable Energy's (EERE's) Hydrogen Storage Grand Challenge Solicitation issued in FY 2003. The Hydrogen Sorption Center of Excellence (HSCoE) focuses on developing high-capacity sorbents with the goal to operate at temperatures and pressures approaching ambient and be efficiently and quickly charged in the tank with minimal energy requirements and penalties to the hydrogen fuel infrastructure. The work was directed at overcoming barriers to achieving DOE system goals and identifying pathways to meet the hydrogen storage system targets. To ensure that the development activities were performed as efficiently as possible, the HSCoE formed complementary, focused development clusters based on the following four sorption-based hydrogen storage mechanisms: 1. Physisorption on high specific surface area and nominally single element materials 2. Enhanced H2 binding in Substituted/heterogeneous materials 3. Strong and/or multiple H2 binding from coordinated but electronically unsatruated metal centers 4. Weak Chemisorption/Spillover. As a member of the team, our group at Duke studied the synthesis of various carbon-based materials, including carbon nanotubes and microporous carbon materials with controlled porosity. We worked closely with other team members to study the effect of pore size on the binding energy of hydrogen to the carbon -based materials. Our initial project focus was on the synthesis and purification of small diameter, single-walled carbon nanotubes (SWNTs) with well-controlled diameters for the study of their hydrogen storage properties as a function of diameters. We developed a chemical vapor deposition method that synthesized gram quantities of carbon nanotubes with average diameter size at less than 1 nm. However, initial tests performed at our collaborator's lab at the National Renewable Energy Laboratory (NREL) did not indicate improved hydrogen sorption properties for the smaller-diameter nanotubes (compared with other types of nanotubes). As work continued, the difficulties in purification, large-scale synthesis, and stability of small diameter SWNTs became a major concern. In 2008, the Department of Energy (DOE) made a no-go decision on future applied R & D investment in pure, undoped, single-walled carbon nanotubes for vehicular hydrogen storage.2 The second phase of the project involved developing a low-cost and scalable approach for the synthesis of microporous carbon materials with well-controlled pore sizes that would be suitable for hydrogen storage. The team studied several approaches, including the use of different zeolites as a template, the use of organic micelle structures as a template, and the slow oxidation of polymer precursors. Among them, the slow activation of Polyether ether ketone (PEEK) under either CO2 environment or H2O vapor produced microporous carbon with an average pore size of less than 2 nm. Initial testing at 77K at both NREL and the California Institute of Technology (CalTech) showed that these materials can store ~5.1 wt% hydrogen (excess) at 40 bar and 77K. The main feature to note with this material is that while the excess gravimetric capacities (>5 wt% at 77K) and specific surface areas (>3100 m2/g) are similar to AX-21 and other "super activated" commercial carbon sorbents at the same temperatures and pressures, due to the smaller pore sizes, bulk densities greater than 0.7 g/ml can be achieved, enabling excess volumetric capacities greater than 35 g/L; more than double that of AX-21.

Download or read book Hydrogen Storage written by Jianjun Liu and published by BoD – Books on Demand. This book was released on 2012-09-05 with total page 282 pages. Available in PDF, EPUB and Kindle. Book excerpt: Hydrogen, as an energy carrier, is widely regarded as a potential cost effective, renewable, and clean energy alternative to petroleum in order to mitigate energy shortage and global climate warming issues that the world is currently facing. However, storage of hydrogen is a substantial challenge, especially for applications in vehicles with fuel cells that use proton-exchange membranes (PEMs). Therefore, scientific community has started focusing their research activities on developing advanced hydrogen storage materials through nanotechnology. The book presents a wide variety of nanostructured materials used for application in hydrogen storage, covering chemical and physical storage approaches. The research topics include computational design, synthesis, processing, fabrication, characterization, properties and applications of nanomaterials in hydrogen storage systems.

Download or read book Hydrogen Storage Technologies written by Mehmet Sankir and published by John Wiley & Sons. This book was released on 2018-07-10 with total page 296 pages. Available in PDF, EPUB and Kindle. Book excerpt: Hydrogen storage is considered a key technology for stationary and portable power generation especially for transportation. This volume covers the novel technologies to efficiently store and distribute hydrogen and discusses the underlying basics as well as the advanced details in hydrogen storage technologies. The book has two major parts: Chemical and electrochemical hydrogen storage and Carbon-based materials for hydrogen storage. The following subjects are detailed in Part I: Multi stage compression system based on metal hydrides Metal-N-H systems and their physico-chemical properties Mg-based nano materials with enhanced sorption kinetics Gaseous and electrochemical hydrogen storage in the Ti-Z-Ni Electrochemical methods for hydrogenation/dehydrogenation of metal hydrides In Part II the following subjects are addressed: Activated carbon for hydrogen storage obtained from agro-industrial waste Hydrogen storage using carbonaceous materials Hydrogen storage performance of composite material consisting of single walled carbon nanotubes and metal oxide nanoparticles Hydrogen storage characteristics of graphene addition of hydrogen storage materials Discussion of the crucial features of hydrogen adsorption of nanotextured carbon-based materials

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 Designing and Building Fuel Cells written by Colleen Spiegel and published by McGraw Hill Professional. This book was released on 2007-05-22 with total page 449 pages. Available in PDF, EPUB and Kindle. Book excerpt: Acquire an All-in-One Toolkit for Expertly Designing, Modeling, and Constructing High-Performance Fuel Cells Designing and Building Fuel Cells equips you with a hands-on guide for the design, modeling, and construction of fuel cells that perform as well or better than some of the best fuel cells on the market today. Filled with over 120 illustrations and schematics of fuel cells and components, this “one-stop” guide covers fuel cell applications...fuels and the hydrogen economy...fuel cell chemistry, thermodynamics, and electrochemistry...fuel cell modeling, materials, and system design...fuel types, delivery, and processing...fuel cell operating conditions...fuel cell characterization...and much more. Authoritative and practical, Designing and Building Fuel Cells features: Complete information on stack design The latest fuel cell modeling techniques Guidance on cutting-edge materials and components Expert accounts of fuel cell types, processing, and optimization A step-by-step example for constructing a fuel cell Inside This State-of-the-Art Fuel Cell Sourcebook Introduction • Fuel Cell Applications • Fuel Cells and the Hydrogen Economy • Basic Fuel Cell Chemistry and Thermodynamics • Fuel Cell Electrochemistry • Fuel Cell Charge Transport • Fuel Cell Mass Transport • Fuel Cell Heat Transport • Fuel Cell Modeling • Fuel Cell Materials • Fuel Cell Stack Components and Materials • Fuel Cell Stack Design • Fuel Cell System Design • Fuel Types, Delivery, and Processing • Fuel Cell Operating Conditions • Fuel Cell Characterization

Download or read book Thermo kinetics of Hydrogen Storage in Arrays of Single walled Carbon Nanotubes written by Ryan Anthony Layton and published by . This book was released on 2004 with total page 44 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Nanomaterials for Solid State Hydrogen Storage written by Robert A. Varin and published by Springer Science & Business Media. This book was released on 2009-01-13 with total page 346 pages. Available in PDF, EPUB and Kindle. Book excerpt: Over the past decade, important advances have been made in the development of nanostructured materials for solid state hydrogen storage used to supply hydrogen to fuel cells in a clean, inexpensive, safe and efficient manner. Nanomaterials for Solid State Hydrogen Storage focuses on hydrogen storage materials having high volumetric and gravimetric hydrogen capacities, and thus having the highest potential of being applied in the automotive sector. Written by leading experts in the field, Nanomaterials for Solid State Hydrogen Storage provides a thorough history of hydrides and nanomaterials, followed by a discussion of existing fabrication methods. The authors’ own research results in the behavior of various hydrogen storage materials are also presented. Covering fundamentals, extensive research results and recent advances in nanomaterials for solid state hydrogen storage, this book serves as a comprehensive reference.

Download or read book Sacr Regi Majestatis Sveciae Literae ad Eminentissimum Dn Electorem Moguntium et in simili ad reliquos Sacri Romani Imperii Electores Principes ac Status written by and published by . This book was released on 1657 with total page 15 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book The Hydrogen Cycle generation Storage and Fuel Cells written by Materials Research Society and published by . This book was released on 2006 with total page 320 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Carbon Nanotubes in Hydrogen Fuel Cells written by Jason Ming-Young Tang and published by . This book was released on 2007 with total page 198 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Kinetics of Carbon Nanotube Growth with Applications in Hydrogen Storage written by Ranadeep Bhowmick and published by . This book was released on 2010 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Carbon nanotubes (CNTs) have unique transport and elastic properties due to their high aspect ratios. Hence there is considerable interest in using these tubes as field emitter cathodes, composite materials with enhanced electrical and mechanical properties, electronic components and recently for hydrogen storage applications taking advantage of the high specific surface areas. In this thesis three different aspects of carbon nanotubes were studied: (1) Controlled growth of single walled nanotubes (SWNTs), (2) Electric field directed Chemical Vapor Deposition (CVD) of multi walled (MWNTs) and (3) "Spillover" Mechanism of hydrogen storage in Pt-SWNT composites. The kinetics of carbon nanotube growth was studied in the context of the CVD process. A generic model for growth of 1-d nano structures via the Vapor-Liquid-Solid (VLS) mechanism is applied to the nanotube growth. This model considers the energetics of individual mass transfer steps through each phase and at the phase interfaces. The flux is then written in terms of the change in chemical potential. Laser interferometry was applied in a cold-wall thermal CVD reactor to measure the growth of the MWNT films in-situ. Temperature dependent studies in the steady-state regime were used to obtain activation energies which are consistent with the interfacial transport step. Consideration of the catalyst activation/de-activation process in the non-steady regimes requires the rate limiting step to be in the vapor-liquid transition. Application of an electric field during the MWNT growth was found to enhance both the growth rate and alignment of the MWNTs. Temperature dependent studies in the presence and absence of the electric field show that there are actually two activated processes involved, with rate-limiting step being independent of applied field at high temperature. At higher temperatures, the rate-limiting step is the carbon dissolution into the catalyst particle, while at lower temperatures it is the carbon dissociation at the catalyst-vapor interface that limits the growth. Application of an electric field enhances the decomposition of the C precursor in the vapor phase, thus circumventing this low temperature activation barrier. The enhanced alignment of the MWNTs with the electric field is explained by tensile stretching overcoming the defect-induced kinking of the MWNTs. Calculations show that this benefit is obtained at a minimum field level, with no benefit arising from further increase in field strength. The catalyst particle size is one of the key parameters that determine the morphology of the 1D carbon nanostructures in both processes studied. The thermodynamics of the nano-particle formation and carbon dissolution are studied and applied to these processes. While the diameter serves to template the CNT diameter, the Gibb's Thompson effect predicts a size dependent suppression of melting point which determines the nature of CNT formed. In the CVD process, higher pressures were found to form larger particle sizes which led to nanofiber growth. At these diameters, the melting point suppression puts the Fe-C particle in a dual solid-liquid phase. Carbon flux accumulates in the dual phase during growth until the dual phase becomes energetically unfavorable. At this point, the particle reverts to a single solid phase regime by discarding excess carbon, resulting in a discontinuous graphitic structure characteristic of Carbon nanofibers. For smaller particles, the phase is entirely liquid and leads to steady state carbon flux and CNT growth. Controlling the iron bearing precursor concentration of the solution fed into the floating catalyst reactor was found to control particle size, and hence SWNT diameter, within this regime. For similar catalyst particle size distributions, increasing the temperature increased the range of SWNT diameters and chiralities obtained. The thermodynamic energy barrier for SWNT formation at the different diameters was calculated and shown to be consistent with the observed variation. Finally, the mechanism of hydrogen uptake in transition metal-doped SWNT was studied. Molecular hydrogen, dissociated by metal catalyst nanoparticles, diffuses to the nanotube surface forming stronger bonds. In-situ 4-probe conductivity tests were performed on mats of Pt doped SWNT during hydrogen uptake. On hydrogen charging the resistivity of the Pt doped SWNT mat increased. This is due to the formation of C-H bonds, which breaks the symmetry of the CNT electronic structure resulting in formation of localized defects, thereby increasing the resistivity. Initial studies of the temporal dependence of hydrogen uptake suggest a diffusion-limited process. XPS was employed to measure the extent of sp3 C-H bonding.

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 Review of the Research Program of the FreedomCAR and Fuel Partnership written by National Research Council and published by National Academies Press. This book was released on 2010-12-23 with total page 228 pages. Available in PDF, EPUB and Kindle. Book excerpt: The public-private partnership to develop vehicles that require less petroleum-based fuel and emit fewer greenhouse gases should continue to include fuel cells and other hydrogen technologies in its research and development portfolio. The third volume in the FreedomCAR series states that, although the partnership's recent shift of focus toward technologies that could be ready for use in the nearer term-such as advanced combustion engines and plug-in electric vehicles-is warranted, R&D on hydrogen and fuel cells is also needed given the high costs and challenges that many of the technologies must overcome before widespread use. The FreedomCAR (Cooperative Automotive Research) and Fuel Partnership is a research collaboration among the U.S. Department of Energy, the United States Council for Automotive Research - whose members are the Detroit automakers-five major energy companies, and two electric utility companies. The partnership seeks to advance the technologies essential for components and infrastructure for a full range of affordable, clean, energy efficient cars and light trucks. Until recently, the program primarily focused on developing technologies that would allow U.S. automakers to make production and marketing decisions by 2015 on hydrogen fuel cell-powered vehicles. These vehicles have the potential to be much more energy-efficient than conventional gasoline-powered vehicles, produce no harmful tailpipe emissions, and significantly reduce petroleum use. In 2009, the partnership changed direction and stepped up efforts to advance, in the shorter term, technologies for reducing petroleum use in combustion engines, including those using biofuels, as well as batteries that could be used in plug-in hybrid-electric or all electric vehicles.

Download or read book PEM Fuel Cell Modeling and Simulation Using Matlab written by Colleen Spiegel and published by Elsevier. This book was released on 2011-08-29 with total page 454 pages. Available in PDF, EPUB and Kindle. Book excerpt: Although, the basic concept of a fuel cell is quite simple, creating new designs and optimizing their performance takes serious work and a mastery of several technical areas. PEM Fuel Cell Modeling and Simulation Using Matlab, provides design engineers and researchers with a valuable tool for understanding and overcoming barriers to designing and building the next generation of PEM Fuel Cells. With this book, engineers can test components and verify designs in the development phase, saving both time and money. Easy to read and understand, this book provides design and modelling tips for fuel cell components such as: modelling proton exchange structure, catalyst layers, gas diffusion, fuel distribution structures, fuel cell stacks and fuel cell plant. This book includes design advice and MATLAB and FEMLAB codes for Fuel Cell types such as: polymer electrolyte, direct methanol and solid oxide fuel cells. This book also includes types for one, two and three dimensional modeling and two-phase flow phenomena and microfluidics. *Modeling and design validation techniques *Covers most types of Fuel Cell including SOFC *MATLAB and FEMLAB modelling codes *Translates basic phenomena into mathematical equations