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36. Boron Hydrogen Compounds: Hydrogen Storage and Battery Applications

Author

Hagemann, Hans

Subjects
Pharmaceutical Science, Organic chemistry, Review, 02 engineering and technology, 010402 general chemistry, 021001 nanoscience & nanotechnology, 01 natural sciences, 0104 chemical sciences, Analytical Chemistry, hydrogen storage, solid ionic conductors, QD241-441, Chemistry (miscellaneous), Drug Discovery, Molecular Medicine, Physical and Theoretical Chemistry, 0210 nano-technology, boron hydrides
Abstract

About 25 years ago, Bogdanovic and Schwickardi (B. Bogdanovic, M. Schwickardi: J. Alloys Compd. 1–9, 253 (1997) discovered the catalyzed release of hydrogen from NaAlH4. This discovery stimulated a vast research effort on light hydrides as hydrogen storage materials, in particular boron hydrogen compounds. Mg(BH4)2, with a hydrogen content of 14.9 wt %, has been extensively studied, and recent results shed new light on intermediate species formed during dehydrogenation. The chemistry of B3H8−, which is an important intermediate between BH4− and B12H122−, is presented in detail. The discovery of high ionic conductivity in the high-temperature phases of LiBH4 and Na2B12H12 opened a new research direction. The high chemical and electrochemical stability of closo-hydroborates has stimulated new research for their applications in batteries. Very recently, an all-solid-state 4 V Na battery prototype using a Na4(CB11H12)2(B12H12) solid electrolyte has been demonstrated. In this review, we present the current knowledge of possible reaction pathways involved in the successive hydrogen release reactions from BH4− to B12H122−, and a discussion of relevant necessary properties for high-ionic-conduction materials.

Published
2021

39. Fe4(OAc)10[EMIM]2: Novel Iron-Based Acetate EMIM Ionic Compound

Author

Severa, Godwin, primary, Bruffey, Edward, additional, Nguyen, Phuong Q. H., additional, Gigante, Angelina, additional, Leick, Noemi, additional, Kelly, Colleen, additional, Finkelstein, Gregory J., additional, Hagemann, Hans, additional, Gennett, Thomas, additional, Rocheleau, Richard E., additional, and Dera, Przemyslaw, additional

Published
2021
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42. Structural and dynamic studies of Pr(11BH4)3

Author

Gigante, Angelina, primary, Payandeh, Seyedhosein, additional, Grinderslev, Jakob B., additional, Heere, Michael, additional, Embs, Jan Peter, additional, Jensen, Torben R., additional, Burankova, Tatsiana, additional, Remhof, Arndt, additional, and Hagemann, Hans, additional

Published
2021
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45. Crystallization of SrAl12O19Nanocrystals from Amorphous Submicrometer Particles

Author

Afshani, Jafar, Perez Mellor, Ariel, Bürgi, Thomas, and Hagemann, Hans

Abstract

Advanced instrumentation and modern analysis tools such as transmission electron microscopy (TEM) have led to phenomenal progress in understanding crystallization, in particular from solution, which is a prerequisite for the design-based preparation of a target crystal. Nevertheless, little has been understood about the crystallization pathway under high-temperature annealing (HTA) conditions. Metal oxide crystals are prominent materials that are usually obtained via HTA. Despite the widespread application of hydro-/solvothermal methods on the laboratory scale, HTA is the preferred method in many industries for the mass production of metal oxide crystals. However, poor control over the morphology and grain sizes of these crystals under extreme HTA conditions limits their applications. Here, applying ex-situ TEM, the transformation of a single amorphous spherical submicrometer precursor particle of SrAl12O19(SA6) at 1150 °C toward a nanosized thermodynamically favored hexagonal crystal is explored. It is illustrated in real space, step by step, how both kinetic and thermodynamic factors contribute to this faceting and morphology evolution. These results demonstrate a nonclassical nucleation and growth process consisting of densification, crystallite domain formation, oriented attachment, surface nucleation, 2-dimensional (2D) growth, and surface diffusion of the atoms to eventually result in the formation of a hexagonal platelet crystal. The TEM images further delineate a parent crystal driving the crystal lattice and morphological orientation of a network of interconnected platelets.

Published
2022
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50. Magnesium-adenosine diphosphate binding sites in wild-type creatine kinase and in mutants: role of aromatic residues probed by Raman and infrared spectroscopies

Author

Hagemann, Hans, Marcillat, Olivier, Buchet, Rene, and Vial, Christian

Subjects
Creatine kinase -- Research, Binding sites (Biochemistry) -- Research, Enzymes -- Structure-activity relationship, Biological sciences, Chemistry
Abstract

The Trp-227 residue of creatine kinase prevents water from reaching the active site and an additional Trp may facilitate nucleotide binding to the active site. Mg-ADP binding does not cause substantial change in the secondary structure of the enzyme.

Published
2000

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