Thermal decomposition of ammonia borane at high pressures

Johanna Nyĺn, Toyoto Sato, Emmanuel Soignard, Jeffery Yarger, Emil Stoyanov, Ulrich Häussermann

Research output: Contribution to journalArticle

40 Scopus citations

Abstract

The effects of high pressure (up to 9 GPa) on the thermal decomposition of ammonia borane, BH3 NH3, were studied in situ by Raman spectroscopy in a diamond anvil cell. In contrast with the three-step decomposition at ambient pressure, thermolysis under pressure releases almost the entire hydrogen content of the molecule in two distinct steps. The residual of the first decomposition is polymeric aminoborane, (BH2 NH 2 x, which is also observed at ambient pressure. The residual after the second decomposition is unique to high pressure. Presumably it corresponds to a precursor to hexagonal BN where macromolecular fragments of planar hexagon layers formed by B and N atoms are terminated by H atoms. Increasing pressure increases the temperature of both decomposition steps. Due to the increased first decomposition temperature it becomes possible to observe a new high pressure, high temperature phase of BH3 NH3 which may represent melting.

Original languageEnglish (US)
Article number104506
JournalJournal of Chemical Physics
Volume131
Issue number10
DOIs
StatePublished - Sep 25 2009

ASJC Scopus subject areas

  • Physics and Astronomy(all)
  • Physical and Theoretical Chemistry

Fingerprint Dive into the research topics of 'Thermal decomposition of ammonia borane at high pressures'. Together they form a unique fingerprint.

  • Cite this

    Nyĺn, J., Sato, T., Soignard, E., Yarger, J., Stoyanov, E., & Häussermann, U. (2009). Thermal decomposition of ammonia borane at high pressures. Journal of Chemical Physics, 131(10), [104506]. https://doi.org/10.1063/1.3230973