Study of the NaBH4–NaBr system and the behaviour of its low temperature phase transition

Research output: Contribution to journalArticle

Authors

  • Christos Paterakis
  • Michael Heere
  • Magnus Sørby
  • Bjørn Hauback

External organisations

  • Institute for Energy Technology, Kjeller

Abstract

A mechano-chemical method was used to synthesize solid solution Na(BH4)1-xBrx with 0 ≤ x ≤ 1. Samples with compositions of x ≤ 0.333 were annealed, in order to form a single phase material. Bromide substitution leads to smaller unit cell size and lower temperature and enthalpy of the order-disorder phase transition of NaBH4. There is a linear relation between the amount of substitution, the temperature, the enthalpy and the kinetics of the phase transition. This linear relation between enthalpy and amount of substitution can be expressed by the function ΔH = −6.268x + 1.206 where x is the amount of substitution and ΔH is the enthalpy.

Details

Original languageEnglish
Pages (from-to)22538-22543
Number of pages6
JournalInternational Journal of Hydrogen Energy
Volume42
Early online date8 Apr 2017
Publication statusE-pub ahead of print - 8 Apr 2017