Hydrogen storage

Abstract: Many potential applications have been proposed for carbon nanotubes, including conductive and high-strength composites; energy storage and energy conversion devices; sensors; field emission displays and radiation sources; hydrogen storage media; and nanometer-sized semiconductor devices, probes, and interconnects. Some of these applications are now realized in products. Others are demonstrated in early to advanced devices, and one, hydrogen storage, is clouded by controversy. Nanotube cost, polydispersity in nanotube type, and limitations in processing and assembly methods are important barriers for some applications of single-walled nanotubes.

Abstract: New materials capable of storing hydrogen at high gravimetric and volumetric densities are required if hydrogen is to be widely employed as a clean alternative to hydrocarbon fuels in cars and other mobile applications. With exceptionally high surface areas and chemically-tunable structures, microporous metal–organic frameworks have recently emerged as some of the most promising candidate materials. In this critical review we provide an overview of the current status of hydrogen storage within such compounds. Particular emphasis is given to the relationships between structural features and the enthalpy of hydrogen adsorption, spectroscopic methods for probing framework–H2 interactions, and strategies for improving storage capacity (188 references).

Abstract: Metal-organic framework-5 (MOF-5) of composition Zn4O(BDC)3 (BDC = 1,4-benzenedicarboxylate) with a cubic three-dimensional extended porous structure adsorbed hydrogen up to 4.5 weight percent (17.2 hydrogen molecules per formula unit) at 78 kelvin and 1.0 weight percent at room temperature and pressure of 20 bar. Inelastic neutron scattering spectroscopy of the rotational transitions of the adsorbed hydrogen molecules indicates the presence of two well-defined binding sites (termed I and II), which we associate with hydrogen binding to zinc and the BDC linker, respectively. Preliminary studies on topologically similar isoreticular metal-organic framework-6 and -8 (IRMOF-6 and -8) having cyclobutylbenzene and naphthalene linkers, respectively, gave approximately double and quadruple (2.0 weight percent) the uptake found for MOF-5 at room temperature and 10 bar.

Abstract: VOLUME 1: FUNDAMENTALS AND SURVEY OF SYSTEMS. Contributors to Volume 1. Foreword. Preface. Abbreviations and Acronyms. Part 1: Thermodynamics and kinetics of fuel cell reactions. Part 2: Mass transfer in fuel cells. Part 3: Heat transfer in fuel cells. Part 4: Fuel cell principles, systems and applications. Contents for Volumes 2, 3 and 4. Subject Index. VOLUME 2: ELECTROCATALYSIS. Contributors to Volume 2. Foreword. Preface. Abbreviations and Acronyms. Part 1: Introduction. Part 2: Theory of electrocatalysis. Part 3: Methods in electrocatalysis. Part 4: The hydrogen oxidation/evolution reaction. Part 5: The oxygen reduction/evolution reaction. Part 6: Oxidation of small organic molecules. Part 7: Other energy conversion related topics. Contents for Volumes 1, 3 and 4. Subject Index. VOLUME 3: FUEL CELL TECHNOLOGY AND APPLICATIONS: PART 1. Contributors to Volumes 3 and 4. Foreword. Preface. Abbreviations and Acronyms. Part 1: Sustainable energy supply. Part 2: Hydrogen storage and hydrogen generation. Development prospects for hydrogen storage. Chemical hydrogen storage devices. Reforming of methanol and fuel processor development. Fuel processing from hydrocarbons to hydrogen. Well-to-wheel efficiencies. Hydrogen safety, codes and standards. Part 3: Polymer electrolyte membrane fuel cell systems (PEMFC). Bipolar plate materials and flow field design. Membrane materials. Electro-catalysts. Membrane-electrode-assembly (MEA). State-of-the-art performance and durability. VOLUME 4: FUEL CELL TECHNOLOGY AND APPLICATIONS, PART 2. Contributors to Volume 3 and 4. Foreword. Preface. Abbreviations and Acronyms. Part 3: Polymer electrolyte membrane fuel cells and systems (PEMFC) (Continued from previous volume). System design and system-specific aspects. Air-supply components. Applications based on PEM-technology. Part 4: Alkaline fuel cells and systems (AFC). Part 5: Phosphoric acid fuel cells and systems (PAFC). Part 6: Direct methanol fuel cells and systems (DMFC). Part 7: Molten carbonate fuel cells and systems (MCFC). Part 8: Solid oxide fuel cells and systems (SOFC). Materials. Stack and system design. New concepts. Part 9: Primary and secondary metal/air cells. Part 10: Portable fuel cell systems. Part 11: Current fuel cell propulsion systems. PEM fuel cell systems for cars/buses. PEM fuel cell systems for submarines. AFC fuel cell systems. Part 12: Electric utility fuel cell systems. Part 13: Future prospects of fuel cell systems. Contents for Volumes 1 and 2. Subject Index.