Open metal–organic frameworks are widely regarded as promising materials for applications1,2,3,4,5,6,7,8,9,10,11,12,13,14,15 in catalysis, separation, gas storage and molecular recognition. Compared to conventionally used microporous inorganic materials such as zeolites, these organic structures have the potential for more flexible rational design, through control of the architecture and functionalization of the pores. So far, the inability of these open frameworks to support permanent porosity and to avoid collapsing in the absence of guest molecules, such as solvents, has hindered further progress in the field14,15. Here we report the synthesis of a metal–organic framework which remains crystalline, as evidenced by X-ray single-crystal analyses, and stable when fully desolvated and when heated up to 300?°C. This synthesis is achieved by borrowing ideas from metal carboxylate cluster chemistry, where an organic dicarboxylate linker is used in a reaction that gives supertetrahedron clusters when capped with monocarboxylates. The rigid and divergent character of the added linker allows the articulation of the clusters into a three-dimensional framework resulting in a structure with higher apparent surface area and pore volume than most porous crystalline zeolites. This simple and potentially universal design strategy is currently being pursued in the synthesis of new phases and composites, and for gas-storage applications.

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Design and synthesis of an exceptionally stable and highly porous metal-organic framework

In the previous paper Ralph Brodd and Martin Winter described the different kinds of batteries and fuel cells. In this paper I will describe lithium batteries in more detail, building an overall foundation for the papers that follow which describe specific components in some depth and usually with an emphasis on the materials behavior. The lithium battery industry is undergoing rapid expansion, now representing the largest segment of the portable battery industry and dominating the computer, cell phone, and camera power source industry. However, the present secondary batteries use expensive components, which are not in sufficient supply to allow the industry to grow at the same rate in the next decade. Moreover, the safety of the system is questionable for the large-scale batteries needed for hybrid electric vehicles (HEV). Another battery need is for a high-power system that can be used for power tools, where only the environmentally hazardous Ni/ Cd battery presently meets the requirements. A battery is a transducer that converts chemical energy into electrical energy and vice versa. It contains an anode, a cathode, and an electrolyte. The anode, in the case of a lithium battery, is the source of lithium ions. The cathode is the sink for the lithium ions and is chosen to optimize a number of parameters, discussed below. The electrolyte provides for the separation of ionic transport and electronic transport, and in a perfect battery the lithium ion transport number will be unity in the electrolyte. The cell potential is determined by the difference between the chemical potential of the lithium in the anode and cathode, ∆G ) -EF. As noted above, the lithium ions flow through the electrolyte whereas the electrons generated from the reaction, Li ) Li+ + e-, go through the external circuit to do work. Thus, the electrode system must allow for the flow of both lithium ions and electrons. That is, it must be both a good ionic conductor and an electronic conductor. As discussed below, many electrochemically active materials are not good electronic conductors, so it is necessary to add an electronically conductive material such as carbon * To whom correspondence should be addressed. Phone and fax: (607) 777-4623. E-mail: stanwhit@binghamton.edu. 4271 Chem. Rev. 2004, 104, 4271−4301

http://www.chemie.uni-regensburg.de/Anorganische_Chemie/Vortrag/StudentenWS06-07/Vortrag_Amereller.pdf

Lithium Batteries and Cathode Materials

Metal–Organic Frameworks for Separations

Kenji Sumida, David L. Rogow, Jarad A. Mason, Thomas M. McDonald, Eric D. Bloch, Zoey R. Herm, Tae-Hyun Bae, Jeffrey R. Long

Carbon Dioxide Capture in Metal–Organic Frameworks

This critical review will be of interest to the experts in porous solids (including catalysis), but also solid state chemists and physicists. It presents the state-of-the-art on hybrid porous solids, their advantages, their new routes of synthesis, the structural concepts useful for their ‘design’, aiming at reaching very large pores. Their dynamic properties and the possibility of predicting their structure are described. The large tunability of the pore size leads to unprecedented properties and applications. They concern adsorption of species, storage and delivery and the physical properties of the dense phases. (323 references)

Hybrid porous solids: past, present, future

Solid oxide fuel cells (SOFCs) have the promise to improve energy efficiency and to provide society with a clean energy producing technology. The high temperature of operation (500−1000 °C) enables the solid oxide fuel cell to operate with existing fossil fuels and to be efficiently coupled with turbines to give very high efficiency conversion of fuels to electricity. Solid oxide fuel cells are complex electrochemical devices that contain three basic components, a porous anode, an electrolyte membrane, and a porous cathode. In this short review, a survey of the types and properties of materials that have been considered for each of these components is presented with an emphasis on the requirements for operation at intermediate temperature (500−800 °C). Some directions for future research are discussed.

Materials for Solid Oxide Fuel Cells

As part of an investigation of new cathode materials for intermediate temperature solid oxide fuel cells, we have investigated particular perovskite oxides with ordered A cations which, in turn, localize the oxygen vacancies into layers. The oxygen exchange kinetics of polycrystalline samples of the oxygen-deficient double perovskite PrBaCo2O5+x (PBCO) have been determined by electrical conductivity relaxation (ECR) and by oxygen-isotope exchange and depth profiling (IEDP). The ECR and IEDP measurements reveal that PBCO has high electronic conductivity and rapid oxygen ion diffusion and surface exchange kinetics. Both techniques demonstrate that the oxygen kinetics in this structure type are significantly faster than in corresponding disordered perovskites.

Rapid oxygen ion diffusion and surface exchange kinetics in PrBaCo2O5+x with a perovskite related structure and ordered A cations

Three compounds were obtained from the reactions of Co(NCS)2 with pyrazine and 4,4‘-bipyridine in different solvents:  Co(NCS)2(pyz)2 (1) has a 2D sheet structure, monoclinic, C2/m, a = 10.039(2) A, b = 10.382(2) A, c = 7.190(1) A, β = 118.64(1)°, Z = 2; Co(NCS)2(H2O)2(4,4‘-bipy)·4,4‘-bipy (2) has linear Co−bipy−Co chains connected by hydrogen bonds between H2O and noncoordinated 4,4‘-bipy molecules to form stair type sheets, triclinic, P1, a = 7.450(1) A, b = 9.020(1) A, c = 10.122(1) A, α = 107.74(1)°, β = 104.02(1)°, γ = 97.16(1)°, Z = 1; Co(NCS)2(4,4‘-bipy)2·2(CH3CH2)2O (3) has ether molecules intercalated between layers formed by Co(NCS)2 and coordinated 4,4‘-bipyridine ligands, monoclinic, P2/c, a = 11.483(2) A, b = 11.397(3) A, c = 13.609(1) A, β = 107.55(1)°, Z = 2. Compounds 2 and 3 thermally decompose to form the same products. The identities of the decomposition products are discussed.

Coordination Polymers of Co(NCS)2 with Pyrazine and 4,4‘-Bipyridine: Syntheses and Structures

Oxygen permeation studies of SrCo0.8Fe0.2O3 − δ

Interlayer chemistry between thick transition-metal oxide layers: synthesis and intercalation reactions of K[Ca2Nan-3NbnO3n+1] (3 .ltoreq. n .ltoreq. 7)

Allan J. Jacobson

Papers

Materials for Solid Oxide Fuel Cells

Rapid oxygen ion diffusion and surface exchange kinetics in PrBaCo2O5+x with a perovskite related structure and ordered A cations

Coordination Polymers of Co(NCS)2 with Pyrazine and 4,4‘-Bipyridine: Syntheses and Structures

Oxygen permeation studies of SrCo0.8Fe0.2O3 − δ

Interlayer chemistry between thick transition-metal oxide layers: synthesis and intercalation reactions of K[Ca2Nan-3NbnO3n+1] (3 .ltoreq. n .ltoreq. 7)