Low temperature phase diagram of NH3BH3
2011 (English)In: Materials Research Society Symposium Proceedings: Proceedings of Symposium EE: Solid-State Chemistry of Inorganic Materials VIII / [ed] P.S. Halasyamani; D.G. Mandrus, K.-S. Choi; S.J. Clarke, Cambridge University Press, 2011, article id 1013090625Conference paper, Published paper (Refereed)
Abstract [en]
The pressure-temperature (p-T) phase diagram of NH3BH3 has been investigated by thermal conductivity measurements up to 1.5 GPa at temperatures between 100 and 300 K, and the phase boundaries between the three known structural phases have been identified. The transformation between the room temperature tetragonal I4mm phase and the low temperature orthorhombic Pmn21 phase (Tc = 218 K at p = 0) shows only a small hysteresis. The transformation into the high pressure orthorhombic Cmc21 phase (at 1.0 GPa near 292 K) has a very strong hysteresis, up to Δp = 0.5 GPa, and below 230 K a fraction of this phase is metastable even at atmospheric pressure.
Place, publisher, year, edition, pages
Cambridge University Press, 2011. article id 1013090625
Series
Materials Research Society Symposium Proceedings, ISSN 0272-9172 ; 1309
Keywords [en]
Ammonia-borane, NH3BH3, high pressure, phase diagram, structure, phase boundary, thermal conductivity, X-ray diffraction, Raman spectroscopy, hydrogen storage, phase transformation
National Category
Condensed Matter Physics
Research subject
Physics
Identifiers
URN: urn:nbn:se:umu:diva-41222DOI: 10.1557/opl.2011.331Scopus ID: 2-s2.0-84856295297OAI: oai:DiVA.org:umu-41222DiVA, id: diva2:405047
Conference
2010 Fall Meeting of the Materials Research Society, Boston Nov 29 - Dec 2 2010
Funder
Swedish Research Council, 621-2010-37322011-03-212011-03-212023-10-02Bibliographically approved